The PARTNER trial of neoadjuvant olaparib in triple-negative breast cancer

PARTNER is a prospective, phase II-III, randomised controlled clinical trial, which recruited patients with Triple Negative Breast Cancer (TNBC)1,2, who were gBRCA wild type (gBRCAwt)3. Patients (n=559) were randomised on a 1:1 basis to neoadjuvant carboplatin with paclitaxel +/- olaparib 150mg twice daily, days 3 to 14, for 4 cycles (gap schedule olaparib, research arm) followed by 3 cycles of anthracycline chemotherapy before surgery. The primary endpoint was pathological complete response (pCR)4, and secondary endpoints included event-free survival (EFS), and overall survival (OS)5. pCR was achieved in 51% in the research arm and 52% in the control arm (p=0.753). Estimated EFS at 36 months in research and control arms were 80% and 79% (log-rank p>0.9); OS were 90% and 87.2% (log-rank p=0.8) respectively. In patients with pCR, estimated EFS at 36 months was 90%, and with non-pCR was 70% (log-rank p < 0.001) and OS was 96% and 83% (log-rank p < 0.001) respectively. Neo-adjuvant olaparib did not improve pCR rates, EFS or OS when added to carboplatin/paclitaxel and anthracycline chemotherapy in patients with TNBC (gBRCAwt). This is in marked contrast to the major benefit of olaparib (gap schedule) in those with gBRCA pathogenic variants (gBRCAm) which is reported separately (gBRCAm article). ClinicalTrials.gov ID NCT03150576.

Expert UK consensus on the definition of high risk of recurrence in HER2-negative early breast cancer: A modified Delphi panel

BACKGROUND

There is currently no standardised definition for patients at high risk of recurrence of human epidermal growth factor receptor 2 (HER2)-negative early breast cancer (eBC; stages 1-3) after surgery. This modified Delphi panel aimed to establish expert UK consensus on this definition, separately considering hormone receptor (HR)-positive and triple-negative (TN) patients.

METHODS

Over three consecutive rounds, results were collected from 29, 24 and 22 UK senior breast cancer oncologists and surgeons, respectively. The first round aimed to determine key risk factors in each patient subgroup; subsequent rounds aimed to establish appropriate risk thresholds. Consensus was pre-defined as ≥70% of respondents.

RESULTS

Expert consensus was achieved on need to assess age, tumour size, tumour grade, number of positive lymph nodes, inflammatory breast cancer and risk prediction tools in all HER2-negative patients. There was additional agreement on use of tumour profiling tests and biomarkers in HR-positive patients, and pathologic complete response (pCR) status in TN patients. Thresholds for high recurrence risk were subsequently agreed. In HR-positive patients, these included age <35 years, tumour size >5 cm (as independent risk factors); tumour grade 3 (independently and combined with other high-risk factors); number of positive nodes ≥4 (independently) and ≥1 (combined). For TN patients, the following thresholds reached consensus, both independently and in combination with other factors: tumour size >2 cm, tumour grade 3, number of positive nodes ≥1.

CONCLUSIONS

The results may be a valuable reference point to guide recurrence risk assessment and decision-making after surgery in the HER2-negative eBC population.

Abstract P3-05-39: Expert consensus on the definition of high risk of recurrence in HER2-negative early breast cancer: a modified Delphi panel

PURPOSE: There is currently no standardised definition for patients at high risk of recurrence of HER2-negative early breast cancer (eBC, stages 1–3) after surgery. Recognising that the assessment of high risk is often multifactorial, the aim of this modified Delphi panel was to establish expert UK consensus on this definition, separately considering HR-positive and triple-negative (TN) patients. METHODS: A total of 45 UK-based clinicians, including breast cancer oncologists and surgeons, were invited to participate. The number of respondents in each of three rounds was 29, 24 and 22 respectively. Statements were developed using the results from a targeted literature review and the guidance of a lead clinician, and comprised free-text, single-choice or numerical formats. The first round aimed to determine which factors are currently used in clinical practice to assess risk of recurrence in the populations of interest. In the subsequent rounds, the objective was to establish thresholds indicative of high risk in a 10-year timeframe for each of the factors retained in Round 1. Between each round, statements were refined, considering the distribution of responses and free-text notes provided by participants. Consensus for single-choice questions was set at a pre-defined threshold of ≥70% of respondents. RESULTS: Consensus was achieved on the need to assess age, tumour size, tumour grade, number of positive nodes, presence of inflammatory breast cancer and one or more risk prediction tools to define high risk of recurrence in all HER2-negative patients. In HR-positive patients, there was agreement on the use of one or more tumour profiling tests and biomarkers to define high risk of recurrence. However, there was no consensus on biomarker use in TN patients, and support for specific biomarkers (such as Ki-67) was conflicting for both sub-populations based on the analysis of free-text notes. Similarly, while there was consensus on the use of pCR status/residual disease to indicate high risk in TN patients, this factor failed to reach consensus for the HR-positive sub-population. Germline BRCA status and menopausal status were not considered to be key factors for risk of recurrence in either biological subtype. In the second and third rounds, thresholds indicative of high recurrence risk were agreed; it should be noted that the free-text responses provided by the participants frequently highlighted that many of the factors should be considered along a continuous scale when assessing the risk of individual patients. In HR-positive patients, these thresholds included: age &lt; 35 years, tumour size &gt;5 cm (each when considered independently from other risk factors); tumour grade 3 (independently or in combination with other factors); number of positive lymph nodes ≥4 when considered independently or ≥1 in combination with other factors. For patients with TN tumours, the following thresholds reached consensus, whether considered independently or in combination with other factors: tumour size &gt;2 cm, tumour grade 3, number of positive lymph nodes ≥1. In several cases, however, no consensus could be reached on the appropriate threshold indicating high risk of recurrence. In the HR-positive sub-population, these included thresholds for age and tumour size, when considered in combination with other factors. In the TN sub-population, this included age, whether independently or in combination with other factors. CONCLUSIONS: The expert consensus reached in this panel highlights that an integrated model is important in assessing recurrence risk in eBC and that definitions of high risk differ according to biological subtype. The results may serve as a valuable reference point for clinicians to use in assessing risk of disease recurrence and in making treatment decisions after surgery in the HER2-negative eBC population. FUNDING: AstraZeneca UK Ltd. Writing support: Costello Medical.

Citation Format: Ellen R. Copson, Jean E. Abraham, Jeremy P. Braybrooke, Stuart A. McIntosh, Caroline O. Michie, Carlo Palmieri, Rebecca Roylance, Saiqa Spensley. Expert consensus on the definition of high risk of recurrence in HER2-negative early breast cancer: a modified Delphi panel [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-05-39.

Circulating tumour DNA analysis to direct therapy in advanced breast cancer (plasmaMATCH): a multicentre, multicohort, phase 2a, platform trial

BACKGROUND

Circulating tumour DNA (ctDNA) testing might provide a current assessment of the genomic profile of advanced cancer, without the need to repeat tumour biopsy. We aimed to assess the accuracy of ctDNA testing in advanced breast cancer and the ability of ctDNA testing to select patients for mutation-directed therapy.

METHODS

We did an open-label, multicohort, phase 2a, platform trial of ctDNA testing in 18 UK hospitals. Participants were women (aged ≥18 years) with histologically confirmed advanced breast cancer and an Eastern Cooperative Oncology Group performance status 0-2. Patients had completed at least one previous line of treatment for advanced breast cancer or relapsed within 12 months of neoadjuvant or adjuvant chemotherapy. Patients were recruited into four parallel treatment cohorts matched to mutations identified in ctDNA: cohort A comprised patients with ESR1 mutations (treated with intramuscular extended-dose fulvestrant 500 mg); cohort B comprised patients with HER2 mutations (treated with oral neratinib 240 mg, and if oestrogen receptor-positive with intramuscular standard-dose fulvestrant); cohort C comprised patients with AKT1 mutations and oestrogen receptor-positive cancer (treated with oral capivasertib 400 mg plus intramuscular standard-dose fulvestrant); and cohort D comprised patients with AKT1 mutations and oestrogen receptor-negative cancer or PTEN mutation (treated with oral capivasertib 480 mg). Each cohort had a primary endpoint of confirmed objective response rate. For cohort A, 13 or more responses among 78 evaluable patients were required to infer activity and three or more among 16 were required for cohorts B, C, and D. Recruitment to all cohorts is complete and long-term follow-up is ongoing. This trial is registered with ClinicalTrials.gov, NCT03182634; the European Clinical Trials database, EudraCT2015-003735-36; and the ISRCTN registry, ISRCTN16945804.

FINDINGS

Between Dec 21, 2016, and April 26, 2019, 1051 patients registered for the study, with ctDNA results available for 1034 patients. Agreement between ctDNA digital PCR and targeted sequencing was 96-99% (n=800, kappa 0·89-0·93). Sensitivity of digital PCR ctDNA testing for mutations identified in tissue sequencing was 93% (95% CI 83-98) overall and 98% (87-100) with contemporaneous biopsies. In all cohorts, combined median follow-up was 14·4 months (IQR 7·0-23·7). Cohorts B and C met or exceeded the target number of responses, with five (25% [95% CI 9-49]) of 20 patients in cohort B and four (22% [6-48]) of 18 patients in cohort C having a response. Cohorts A and D did not reach the target number of responses, with six (8% [95% CI 3-17]) of 74 in cohort A and two (11% [1-33]) of 19 patients in cohort D having a response. The most common grade 3-4 adverse events were raised gamma-glutamyltransferase (13 [16%] of 80 patients; cohort A); diarrhoea (four [25%] of 20; cohort B); fatigue (four [22%] of 18; cohort C); and rash (five [26%] of 19; cohort D). 17 serious adverse reactions occurred in 11 patients, and there was one treatment-related death caused by grade 4 dyspnoea (in cohort C).

INTERPRETATION

ctDNA testing offers accurate, rapid genotyping that enables the selection of mutation-directed therapies for patients with breast cancer, with sufficient clinical validity for adoption into routine clinical practice. Our results demonstrate clinically relevant activity of targeted therapies against rare HER2 and AKT1 mutations, confirming these mutations could be targetable for breast cancer treatment.

FUNDING

Cancer Research UK, AstraZeneca, and Puma Biotechnology.

Pitfalls in assessing stromal tumor infiltrating lymphocytes (sTILs) in breast cancer

Stromal tumor-infiltrating lymphocytes (sTILs) are important prognostic and predictive biomarkers in triple-negative (TNBC) and HER2-positive breast cancer. Incorporating sTILs into clinical practice necessitates reproducible assessment. Previously developed standardized scoring guidelines have been widely embraced by the clinical and research communities. We evaluated sources of variability in sTIL assessment by pathologists in three previous sTIL ring studies. We identify common challenges and evaluate impact of discrepancies on outcome estimates in early TNBC using a newly-developed prognostic tool. Discordant sTIL assessment is driven by heterogeneity in lymphocyte distribution. Additional factors include: technical slide-related issues; scoring outside the tumor boundary; tumors with minimal assessable stroma; including lymphocytes associated with other structures; and including other inflammatory cells. Small variations in sTIL assessment modestly alter risk estimation in early TNBC but have the potential to affect treatment selection if cutpoints are employed. Scoring and averaging multiple areas, as well as use of reference images, improve consistency of sTIL evaluation. Moreover, to assist in avoiding the pitfalls identified in this analysis, we developed an educational resource available at www.tilsinbreastcancer.org/pitfalls.

Report on computational assessment of Tumor Infiltrating Lymphocytes from the International Immuno-Oncology Biomarker Working Group

Assessment of tumor-infiltrating lymphocytes (TILs) is increasingly recognized as an integral part of the prognostic workflow in triple-negative (TNBC) and HER2-positive breast cancer, as well as many other solid tumors. This recognition has come about thanks to standardized visual reporting guidelines, which helped to reduce inter-reader variability. Now, there are ripe opportunities to employ computational methods that extract spatio-morphologic predictive features, enabling computer-aided diagnostics. We detail the benefits of computational TILs assessment, the readiness of TILs scoring for computational assessment, and outline considerations for overcoming key barriers to clinical translation in this arena. Specifically, we discuss: 1. ensuring computational workflows closely capture visual guidelines and standards; 2. challenges and thoughts standards for assessment of algorithms including training, preanalytical, analytical, and clinical validation; 3. perspectives on how to realize the potential of machine learning models and to overcome the perceptual and practical limits of visual scoring.

Treating Brain Metastases from Breast Cancer: Outcomes after Stereotactic Radiosurgery

AIMS

Stereotactic radiosurgery (SRS) is an alternative to surgery or whole brain radiotherapy for the control of single or multiple brain metastases in patients with breast cancer. To date, there is no clear consensus on factors that might predict overall survival following SRS. The aim of this study was to assess the overall survival of breast cancer patients with brain metastases treated with SRS at a single centre and to examine the factors that might influence survival.

MATERIALS AND METHODS

A retrospective analysis of consecutive patients with breast cancer and brain metastases, considered suitable for SRS by the regional neuro-oncology multidisciplinary team. All patients were treated at a single National Health Service centre.

RESULTS

In total, 91 patients received SRS between 2013 and 2017, of whom 15 (16.5%) were alive at the time of analysis. The median overall survival post-SRS was 15.7 months (interquartile range 7.7-23.8 months) with no significant effect of age on survival (67 patients ≤ 65 years, 16.3 months; 26 patients > 65 years, 11.4 months, P = 0.129). The primary tumour receptor status was an important determinant of outcome: 31 oestrogen receptor positive (ER+)/human epidermal growth factor receptor 2 negative (HER2-) patients had a median overall survival of 13.8 months, 14 ER+/HER2+ patients had a median overall survival of 21.4 months, 30 ER-/HER2+ patients had a median overall survival of 20.4 months and 16 patients with triple negative breast cancer (TNBC) had a median overall survival of 8.5 months. A larger total volume of tumour treated (>10 cm³), but not the number of individual metastases treated, was associated with worse survival (P = 0.0002) in this series. Patients with stable extracranial disease at the time of SRS had improved overall survival compared with those with progressive extracranial disease (30 patients stable extracranial disease overall survival = 20.1 months versus 33 patients progressive extracranial disease overall survival = 11.4 months; P = 0.0011). Seventeen patients had no extracranial disease at the time of SRS, with a median overall survival of 13.1 months.

CONCLUSIONS

This single-centre series of consecutive patients with brain metastases from breast cancer, treated with SRS, had a similar overall survival compared with previous studies of SRS. TNBC and ER+/HER2- histology, metastatic volumes >10 cm³ and progressive extracranial disease at the time of SRS were associated with worse survival.

Abstract P1-19-11: Results from plasmaMATCH trial treatment cohort C: A phase II trial of capivasertib plus fulvestrant in ER positive breast cancer patients with an AKT1 mutation identified via ctDNA screening (CRUK/15/010)

Background: AKT1 mutation occurs in approximately 3% of breast cancer (BC), enriched in advanced BC. The AKT1 E17K mutation results in constitutive activation of AKT1, associated with sensitivity to AKT inhibitor capivasertib in pre-clinical models, and in a prior phase I trial with AKT1 mutations identified through tumour testing. The plasmaMATCH trial Cohort C assessed the efficacy of capivasertib and fulvestrant in ER positive BC patients with an AKT1 mutation in ctDNA testing.

Methods: The plasmaMATCH trial was an open-label, multi-centre, multi-cohort platform trial, consisting of ctDNA testing in ~1000 patients with advanced BC. Patients with an AKT1 mutation identified via ctDNA testing were registered to Cohort C. Patients were treated with capivasertib 400mg BID 4 days on - 3 days off, plus fulvestrant 500mg intramuscularly on Cycle 1 Days 1 and 15, and Cycle 2 onwards every 28 days. The primary endpoint for Cohort C was confirmed objective response rate as defined by RECIST v1.1. Using a single stage A’Hern design with a target response rate of 25%, unacceptable response rate of 5%, alpha=5% and power=80%, at least 3 responses out of 16 evaluable patients were required to infer efficacy.

Results: Following ctDNA testing, 18 patients enrolled in Cohort C (42% of patients with AKT1 mutations identified in ctDNA testing). All were ER positive, 1 (5.6%) was HER2 amplified, and 17 (94%) had visceral metastases. Mutation was AKT1 E17K in 17 patients and AKT1 L52R in 1 patient. All patients were evaluable with a confirmed response rate of 22.2% (95%CI 6.4-47.6%, 4/18) (first 16 evaluable patients: 3/16, 18.8% (95%CI 4.0-45.6)). A further 4 patients had an unconfirmed partial response. Median progression free survival was 10.2 months (IQR 3.2-18.2 months) and the median duration of response was 7.5 months (IQR 4.1-9.8 months) with 4 patients continuing on treatment. The most common clinically significant grade 3 or 4 adverse events were fatigue (22%), rash (17%), diarrhoea (11%) and hyperglycaemia (11%).

Conclusions: Capivasertib plus fulvestrant was active in patients with ER positive breast cancer and AKT1 mutations identified in ctDNA testing, meeting the pre-specified threshold for efficacy

Citation Format: Rebecca Roylance, Lucy Kilburn, Sarah Kernaghan, Andrew M Wardley, Iain Macpherson, Richard D Baird, Peter Stephens, Olga Oikonomidou, Jeremy P Braybrooke, Mark Tuthill, Jacinta Abraham, Matthew C Winter, Belinda Kingston, Katie Wilkinson, Alistair Ring, Judith M Bliss, Nicholas Turner, on behalf of the plasmaMATCH Trial Management Group. Results from plasmaMATCH trial treatment cohort C: A phase II trial of capivasertib plus fulvestrant in ER positive breast cancer patients with an AKT1 mutation identified via ctDNA screening (CRUK/15/010) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-11.

Abstract P1-19-07: Results from plasmaMATCH trial treatment cohort B: A phase II trial of neratinib plus fulvestrant in ER positive breast cancer or neratinib alone in ER negative breast cancer in patients with a HER2 mutation identified via ctDNA screening (CRUK/15/010)

Background: HER2 mutations occur in approximately 3% of HER2 non-amplified cancers and include missense substitutions and indels within the tyrosine kinase domain resulting in oncogenic HER2 activation. Neratinib, an irreversible EGFR, HER2 and ERBB4 tyrosine kinase inhibitor, has demonstrated activity in pre-clinical HER2 mutant models, and in a prior phase I trial with HER2 mutations identified through tumour testing. The plasmaMATCH trial Cohort B assessed the efficacy of neratinib in BC patients with a HER2 mutation identified in ctDNA testing.

Methods: The plasmaMATCH trial was an open-label, multi-centre, multi-cohort platform trial, consisting of ctDNA testing in ~1000 patients with advanced BC. Patients with a HER2 mutation identified via ctDNA testing were registered to Cohort B. Patients were treated with 240mg neratinib once daily. Patients with ER positive BC were also treated with fulvestrant 500mg intramuscularly on Cycle 1 Days 1 and 15, and Cycle 2 onwards every 28 days. The primary endpoint for Cohort B was confirmed objective response rate as defined by RECIST v1.1. Using a single stage A’Hern design with a target response rate of 25%, unacceptable response rate of 5%, alpha=5% and power=80%, at least 3 responses out of 16 evaluable patients were required to infer efficacy.

Results: Following ctDNA testing, 21 patients enrolled in Cohort B (58% of patients with HER2 mutations identified in ctDNA testing). Eighteen (86%) were ER positive, 2 (10%) were HER2 amplified, and 18 (86%) had visceral metastases. The most common HER2 mutations detected in baseline plasma were L755S (47.6%), V777L (19%), and S310F (14.3%). In the 20 evaluable patients, confirmed response rate was 25.0% (95%CI 8.7-49.1%, 5/20) (first 16 evaluable patients: 4/16, 25.0% (95%CI 7.3-52.4)). One patient had a complete response, ongoing at 29 months duration, and three additional patients had unconfirmed partial responses. Median progression free survival was 5.4 months (IQR 3.4-9.1) and median duration of response was 5.7 months (IQR 3.7-9.7 months) with 3 patients continuing on treatment. The most common clinically significant grade 3 or 4 adverse events were diarrhoea (20%) and hypertension (15%).

Conclusions: Neratinib, with or without fulvestrant, was active in advanced BC patients with HER2 mutations identified in ctDNA testing, meeting the pre-specified threshold for efficacy.

Citation Format: Andrew M Wardley, Lucy Kilburn, Sarah Kernaghan, Iain Macpherson, Richard D Baird, Rebecca Roylance, Peter Stephens, Olga Oikonomidou, Jeremy P Braybrooke, Mark Tuthill, Jacinta Abraham, Matthew C Winter, Belinda Kingston, Katie Wilkinson, Judith M Bliss, Alistair Ring, Nicholas Turner, on behalf of the plasmaMATCH Trial Management Group. Results from plasmaMATCH trial treatment cohort B: A phase II trial of neratinib plus fulvestrant in ER positive breast cancer or neratinib alone in ER negative breast cancer in patients with a HER2 mutation identified via ctDNA screening (CRUK/15/010) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-07.

Abstract GS3-06: Results from the plasmaMATCH trial: A multiple parallel cohort, multi-centre clinical trial of circulating tumour DNA testing to direct targeted therapies in patients with advanced breast cancer (CRUK/15/010)

Background: Circulating tumour DNA (ctDNA) testing may provide a more current assessment of the genetic profile of advanced breast cancer (BC) compared with analysis of the primary tumour, with repeat advanced disease biopsy conducted infrequently in routine clinical practice. The plasmaMATCH trial was designed to assess the clinical utility of using ctDNA testing to select patients for targeted therapies.

Methods: The plasmaMATCH trial was an open-label, multi-centre, multi-cohort platform trial, consisting of ctDNA testing in ~1000 patients with advanced BC, with patients recruited into four parallel treatment cohorts with therapies matched to mutations identified in ctDNA (A: ESR1 mutation - extended-dose fulvestrant 500mg every 2 weeks, B: HER2 mutation - neratinib +/- fulvestrant (standard dosing), C: AKT1 in ER positive BC -capivasertib + fulvestrant (standard dosing), D: AKT1 in ER negative BC or PTEN inactivating mutation - capivasertib). A fifth cohort (E) recruited patients with triple negative BC with no actionable mutation to receive olaparib + AZD6738, and will be reported separately. Each cohort had a specific phase II single arm design. ctDNA testing was conducted with two technologies: digital droplet PCR (ddPCR) at a central laboratory prospectively in all patients, and error corrected sequencing with Guardant360 prospectively from part-way through recruitment and retrospectively for the remaining patients. Tumour sequencing from an advanced disease biopsy was conducted retrospectively, not influencing cohort entry. The primary endpoint for Cohorts A-D is confirmed objective response rate by RECIST v1.1. Secondary endpoints include clinical benefit rate, progression-free survival, safety and frequency of mutations identified in ctDNA screening.

Results: Entry into ctDNA testing for Cohorts A-D was closed on 26/Apr/2019 with 1044 patients registered. ctDNA screening results were received for 1033 patients (99%), with 142 patients entered into Cohorts A-D (A 84, B 21, C 18, D 19). Agreement between ctDNA digital PCR and sequencing results was high (individual gene level agreement 95.5%-99.4%, kappa 0.89-0.93). Predefined efficacy criteria were met in Cohorts B (neratinib for HER2 mutations) and C (capivasertib for AKT mutations), with exploratory analysis of Cohort D identifying activity of capivasertib in AKT1 mutations (Table 1). Efficacy criteria were not met in Cohort A (extended-dose fulvestrant for ESR1 mutations). Adverse events were consistent with prior reports, with extended-dose fulvestrant well tolerated.

Table 1: Efficacy results from plasmaMATCHMutationCohortConfirmed response rate, % (95%CI; n/N)Median PFS (IQR), monthsAll patientsFirst 16 evaluable patients*ESR1A8.1% (3.0-16.8; 6/74)-2.2 (1.7-5.3)HER2B25.0% (8.7-49.1; 5/20)25.0% (7.3-52.4; 4/16)5.4 (3.4-9.1)AKT1C22.2% (6.4-47.6; 4/18)18.8% (4.0-45.6; 3/16)10.2 (3.2-18.2)AKT basketD10.5% (1.3-33.1; 2/19)12.5% (1.6-38.3; 2/16)3.4 (1.8-5.5)AKT133.3% (4.3-77.7; 2/6)--PTEN0 % (0/13)--*Predefined cohort efficacy thresholds for response were set: 13/78 (A); 3/16 (B, C, D)

Conclusion: Circulating tumour DNA testing offers accurate tumour genotyping, sufficient for routine clinical practice. This approach can be used to identify patients with rare HER2 and AKT1 mutations, who have clinically relevant response rates with matched targeted therapies.

Citation Format: Nicholas Turner, Belinda Kingston, Lucy Kilburn, Sarah Kernaghan, Andrew M Wardley, Iain Macpherson, Richard D Baird, Rebecca Roylance, Peter Stephens, Olga Oikonomidou, Jeremy P Braybrooke, Mark Tuthill, Jacinta Abraham, Matthew C Winter, Hannah Bye, Michael Hubank, Claire Snowdon, Daniel Rea, David Cameron, Abeer Shaaban, Katrina Randle, Katie Wilkinson, Laura Moretti, Judith M Bliss, Alistair Ring, on behalf of the plasmaMATCH Trial Management Group. Results from the plasmaMATCH trial: A multiple parallel cohort, multi-centre clinical trial of circulating tumour DNA testing to direct targeted therapies in patients with advanced breast cancer (CRUK/15/010) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr GS3-06.

Abstract P1-19-04: Results from plasmaMATCH trial treatment cohort A: A phase II trial of extended-dose fulvestrant in patients with an ESR1 mutation identified via ctDNA screening (CRUK/15/010)

Background: Ligand binding domain ESR1 mutations are acquired in ER positive cancers during prior aromatase inhibitor therapy for advanced ER positive breast cancer (BC). ESR1 mutant cancer models are sensitive to fulvestrant at high concentrations, however standard dose fulvestrant may not achieve the concentration required to fully inhibit mutant ESR1 in the clinic. The plasmaMATCH trial Cohort A assessed the efficacy of extended-dose fulvestrant (double the current standard dose achieved by doubling the frequency of administration) in patients with an ESR1 mutation identified via ctDNA testing.

Methods: The plasmaMATCH trial was an open-label, multi-centre, multi-cohort platform trial, consisting of ctDNA testing in ~1000 patients with advanced BC. Patients with an ESR1 mutation identified in ctDNA testing were potentially eligible to enter Cohort A. Patients were treated with fulvestrant 500mg intramuscularly on Cycle 1 Days 1, 8 and 15 of a 28 day cycle, and from Cycle 2 onwards every 15 days. Pharmacokinetics samples were collected pre-dose on Day 1 of Cycles 2, 3 and 4. The primary endpoint for Cohort A was confirmed objective response rate as defined by RECIST v1.1. The original planned sample size was 40 patients, to detect a 25% response rate, assuming predominantly clonally dominant mutations. As the trial progressed it became apparent that ctDNA screening may also detect sub clonal ESR1 mutations, which were expected to have a lower response rate. Using a single-stage A’Hern design with a target response rate of 20%, unacceptable response rate of 10%, alpha=5%, power=80, the sample size was increased to 78 evaluable patients with 13 or more responses required to infer efficacy.

Results: Following ctDNA testing, 84 patients enrolled in Cohort A (38% of patients with ESR1 mutations identified in ctDNA testing). All were ER positive, seven were HER2 amplified, 78 (93%) had visceral metastases. The most common ESR1 mutations detected in baseline plasma were D538G (52.4%), Y537S (35.7%), E380Q (33.3%). In the 74 evaluable patients, confirmed response rate was 8.1% (95%CI 3.0-16.8%, 6/74). One additional patient had an unconfirmed partial response. Median progression free survival was 2.2 months (IQR 1.7-5.3 months) and median duration of response was 7.0 months (IQR 3.7-8.3 months) with 4 patients continuing on treatment. In exploratory analysis, 39 patients had clonally dominant ESR1 mutations in baseline ctDNA analysis whilst 25 patients had subclonal mutations and 10 had unknown clonality. The response rate in those with clonally dominant ESR1 mutations was 10% (95%CI: 2.9-24.2%, 4/39) with no confirmed responses in those with subclonal mutations. The most common clinically significant grade 3 or 4 adverse event was hypertension (13%). Pharmacokinetic analysis was consistent with elevated fulvestrant exposure compared to approved 500mg PopPk model (pre-dose Cycle 3, 71% increase, and pre-dose Cycle 4 66% increase).

Conclusion: In the pre-treated population studied, the response rate of extended-dose fulvestrant did not meet pre-specified criteria for efficacy in patients with ESR1 mutations identified in ctDNA testing. Extended-dose fulvestrant was well tolerated and enhanced exposure was observed. Assessment of clonal dominance of ESR1 mutations in ctDNA may identify patients who are more likely to benefit from extended-dose fulvestrant therapy.

Citation Format: Iain Macpherson, Lucy Kilburn, Sarah Kernaghan, Andrew M Wardley, Richard D Baird, Rebecca Roylance, Peter Stephens, Olga Oikonomidou, Jeremy P Braybrooke, Mark Tuthill, Jacinta Abraham, Matthew C Winter, Belinda Kingston, Katie Wilkinson, Alistair Ring, Judith M Bliss, Nicholas Turner, on behalf of the plasmaMATCH Trial Management Group. Results from plasmaMATCH trial treatment cohort A: A phase II trial of extended-dose fulvestrant in patients with an ESR1 mutation identified via ctDNA screening (CRUK/15/010) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-04.

The impact of the 21-gene assay on adjuvant treatment decisions in oestrogen receptor-positive early breast cancer: a prospective study

BACKGROUND

International guidelines, including NICE, recommend using the 21-gene Recurrence Score assay for guiding adjuvant treatment decisions in ER+, HER2-negative early breast cancer (BC). We investigated the impact of adding this assay to standard pathological tests on clinicians'/patients' treatment decisions and on patients' decisional conflict in the United Kingdom.

METHODS

In this prospective multicentre study, eligibility criteria included: ER+ HER2-negative BC (N0/Nmic for patients ⩽50 years; ⩽3 positive lymph nodes for patients >50 years) and being fit for chemotherapy. Physicians'/patients' treatment choices and patients' decisional conflict were recorded pre- and post testing.

RESULTS

The analysis included 137 patients. Overall, adjuvant treatment recommendations changed in 40.7% of patients, with the direction of the change consistent with the Recurrence Score results (net decrease in chemotherapy recommendation rate in low Recurrence Score patients and net increase in high Recurrence Score patients). Patients' choices were generally consistent with physicians' recommendations. Post-testing, patients' decisional conflict decreased significantly (P<0.0001). In the 67 patients meeting the NICE criteria for testing, the recommendation change rate was 49.3%.

CONCLUSIONS

Recurrence Score testing significantly influenced treatment recommendations overall and in the subgroup of patients meeting the NICE criteria, suggesting that this test could substantially alter treatment patterns in the United Kingdom.

The effect of chemotherapy on health-related quality of life in mesothelioma: results from the SWAMP trial

Background:

The effect of chemotherapy on health-related quality of life (HRQoL) in malignant pleural mesothelioma (MPM) is poorly understood. Patient-individualised prognostication and prediction of treatment response from chemotherapy is useful but little evidence exists to guide practice.

Method:

Consecutive patients with MPM who were fit for first-line chemotherapy with pemetrexed and cisplatin\carboplatin were recruited and followed up for a minimum of 12 months. This study focussed on the HRQoL outcomes of these patients using the EQ-5D, EORTC QLQ-C30 and LC13.

Results:

Seventy-three patients were recruited of which 58 received chemotherapy and 15 opted for best supportive care (BSC). Compliance with HRQoL questionnaires was 98% at baseline. The chemotherapy group maintained HRQoL compared with the BSC group whose overall HRQoL fell (P=0.006) with worsening dyspnoea and pain. The impact of chemotherapy was irrespective of histological subtype although those with non-epithelioid disease had worse HRQoL at later time points (P=0.012). Additionally, those with a falling mesothelin or improvement on modified-RECIST CT at early follow-up had a better HRQoL at 16 weeks.

Conclusions:

HRQoL was maintained following chemotherapy compared with a self-selected BSC group. Once chemotherapy is initiated, a falling mesothelin or improved RECIST CT findings infer a quality-of-life advantage.

Patients' experiences following breast cancer treatment: an exploratory survey of personal and work experiences of breast cancer patients from three European countries

Improved treatments for early breast cancer have led to a significant increase in overall survival. While evidence regarding potential long-term sequelae of adjuvant treatments exists, relatively little research reports patients' own perceptions of change before and after adjuvant chemotherapy (AC). This study aimed to identify key ongoing issues associated with AC in daily life. An online survey developed for this study was completed by 198 women (mean age 49.7 years) in the UK, France and Germany who had AC 1-5 years previously for oestrogen receptor positive, HER2 negative early breast cancer. Women without AC and endocrine therapy, those treated with Trastuzumab or who had recurrent disease were excluded. A third of women who responded were currently unable to perform their former family role. The majority had needed support, particularly with child care, during treatment. While 54% were in full-time employment before diagnosis this had reduced to 32% following AC. Of those women still working, over half reported difficulties with tiredness or concentration. Most (85.8%) were satisfied with healthcare professionals' treatment information, but only 29.7% received information about returning to work. This exploratory survey highlights areas of women's lives affected 1-5 years following AC for early breast cancer. The impact on returning to work and issues surrounding childcare particularly, require further study.

Fulvestrant plus anastrozole or placebo versus exemestane alone after progression on non-steroidal aromatase inhibitors in postmenopausal patients with hormone-receptor-positive locally advanced or metastatic breast cancer (SoFEA): a composite, multicentre, phase 3 randomised trial

BACKGROUND

The optimum endocrine treatment for postmenopausal women with advanced hormone-receptor-positive breast cancer that has progressed on non-steroidal aromatase inhibitors (NSAIs) is unclear. The aim of the SoFEA trial was to assess a maximum double endocrine targeting approach with the steroidal anti-oestrogen fulvestrant in combination with continued oestrogen deprivation.

METHODS

In a composite, multicentre, phase 3 randomised controlled trial done in the UK and South Korea, postmenopausal women with hormone-receptor-positive breast cancer (oestrogen receptor [ER] positive, progesterone receptor [PR] positive, or both) were eligible if they had relapsed or progressed with locally advanced or metastatic disease on an NSAI (given as adjuvant for at least 12 months or as first-line treatment for at least 6 months). Additionally, patients had to have adequate organ function and a WHO performance status of 0-2. Participants were randomly assigned (1:1:1) to receive fulvestrant (500 mg intramuscular injection on day 1, followed by 250 mg doses on days 15 and 29, and then every 28 days) plus daily oral anastrozole (1 mg); fulvestrant plus anastrozole-matched placebo; or daily oral exemestane (25 mg). Randomisation was done with computer-generated permuted blocks, and stratification was by centre and previous use of an NSAI as adjuvant treatment or for locally advanced or metastatic disease. Participants and investigators were aware of assignment to fulvestrant or exemestane, but not of assignment to anastrozole or placebo. The primary endpoint was progression-free survival (PFS). Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, numbers NCT00253422 (UK) and NCT00944918 (South Korea).

FINDINGS

Between March 26, 2004, and Aug 6, 2010, 723 patients underwent randomisation: 243 were assigned to receive fulvestrant plus anastrozole, 231 to fulvestrant plus placebo, and 249 to exemestane. Median PFS was 4·4 months (95% CI 3·4-5·4) in patients assigned to fulvestrant plus anastrozole, 4·8 months (3·6-5·5) in those assigned to fulvestrant plus placebo, and 3·4 months (3·0-4·6) in those assigned to exemestane. No difference was recorded between the patients assigned to fulvestrant plus anastrozole and fulvestrant plus placebo (hazard ratio 1·00, 95% CI 0·83-1·21; log-rank p=0·98), or between those assigned to fulvestrant plus placebo and exemestane (0·95, 0·79-1·14; log-rank p=0·56). 87 serious adverse events were reported: 36 in patients assigned to fulvestrant plus anastrozole, 22 in those assigned to fulvestrant plus placebo, and 29 in those assigned to exemestane. Grade 3-4 adverse events were rare; the most frequent were arthralgia (three in the group assigned to fulvestrant plus anastrozole; seven in that assigned to fulvestrant plus placebo; eight in that assigned to exemestane), lethargy (three; 11; 11), and nausea or vomiting (five; two; eight).

INTERPRETATION

After loss of response to NSAIs in postmenopausal women with hormone-receptor-positive advanced breast cancer, maximum double endocrine treatment with 250 mg fulvestrant combined with oestrogen deprivation is no better than either fulvestrant alone or exemestane.

Coherent ultrasonic Doppler tomography

Ultrasonic imaging based on the pulse-echo principle is widely used throughout the world, particularly in medical applications. However, its spatial resolution is poor (around 2 times the wavelength, or 200 μm at 15 MHz), limiting its ability to detect small but clinically important lesions (such as microcalcifications in breast cancer). The work presented here is different from the traditional approach. Continuous-wave ultrasound is transmitted to insonate a rotating object, then the amplitude and phase of the returned signals are coherently processed to reconstruct a Doppler tomographic image of the object's backscatter field. It is demonstrated numerically that the spatial resolution is up to 0.19 wavelengths and the sampling requirement and image formation method are given. To show the performance of the method, we present the results obtained by applying the new technique in simulation and experiment. A string phantom consisting of very thin copper wires and two cylindrical phantoms constructed by tissue-mimicking-material were scanned. It is demonstrated that the copper wires were located very accurately with very high spatial resolution, and good shape approximation for the cylindrical phantoms was achieved.

A prospective randomised phase II trial of thalidomide with carboplatin compared with carboplatin alone as a first-line therapy in women with ovarian cancer, with evaluation of potential surrogate markers of angiogenesis

OBJECTIVES

To compare the safety and efficacy of thalidomide in combination with carboplatin to carboplatin alone as a first-line therapy in women with ovarian cancer and to evaluate the anti-angiogenic effects of thalidomide by measurement of surrogate markers of angiogenesis.

METHODS

Forty patients with Stage IC-IV ovarian cancer were randomly assigned to receive either carboplatin (AUC 7) intravenously every four weeks for up to six doses (n = 20) or carboplatin at the same dose and schedule, plus thalidomide 100 mg orally daily for six months (n = 20).

RESULTS

After median follow-up of 1.95 years, there was no difference in the overall response rate (90% in carboplatin arm, 75% in combination arm; p = 0.41). Increased incidence of symptoms of constipation, dizziness, tiredness and peripheral neuropathy was observed in the combination arm. There was a significant fall in CA-125 and E-selectin in both arms after treatment and VCAM-1 in the carboplatin arm. No significant difference between the two arms was observed in any of the markers analysed.

CONCLUSIONS

In our trial the addition of thalidomide to carboplatin was well tolerated with no increased efficacy. The fall in some of the angiogenic markers in both groups may reflect tumour response rather than any specific anti-angiogenic effect of thalidomide.

Pharmacokinetically guided phase I trial of topotecan and etoposide phosphate in recurrent ovarian cancer

A pharmacokinetically guided phase I study of topotecan and etoposide phosphate was conducted in recurrent ovarian cancer. The scheduling of the topoisomerase I and II inhibitors was determined using in vitro activity data. All patients had recurrent disease following prior platinum-containing chemotherapy. Patients had a World Health Organisation performance status of 0–2 and adequate bone marrow, renal and hepatic function. Treatment was with topotecan intravenously for 5 days followed immediately by a 5-day intravenous infusion of etoposide phosphate (EP), with pharmacokinetically guided dose adjustment. Plasma etoposide levels were measured on days 2 and 4 of the infusion. A total of 21 patients entered the study. In all, 48% were platinum resistant and 71% had received prior paclitaxel. The main toxicities were haematological, short lived and reversible. A total of 29% of patients experienced grade 4 thrombocytopenia and 66% grade 4 neutropenia after the first cycle. Neutropenia and thrombocytopenia was dose limiting. The maximum-tolerated dose was topotecan 0.85 mg m⁻² day⁻¹ days 1–5 followed immediately by a 5-day infusion of EP at a plasma concentration of 1 μg ml⁻¹. The response rate (RR) was 28% in 18 evaluable patients. There was marked interpatient variability in topoisomerase IIα levels measured from peripheral lymphocytes, with no observed increase following topotecan. This regimen of topotecan followed by EP demonstrated good activity in recurrent ovarian cancer and was noncrossresistant with paclitaxel. Both the toxicity and RR was higher than would be expected from the single agent data, in keeping with synergy of action.

Study of etanercept, a tumor necrosis factor-alpha inhibitor, in recurrent ovarian cancer

PURPOSE

Convincing data support the link between inflammation and ovarian cancer. Tumor necrosis factor-alpha (TNF-alpha), a major mediator of inflammation, is chronically produced in the ovarian tumor microenvironment and may enhance tumor growth and invasion by inducing the secretion of cytokines, proangiogenic factors, and metalloproteinases. Etanercept is a recombinant human soluble p75 TNF receptor that binds to TNF-alpha and renders it biologically unavailable. In the current study, we sought to determine the toxicity, biologic activity, and therapeutic efficacy of etanercept in recurrent ovarian cancer.

PATIENTS AND METHODS

We initiated a phase I-B, nonrandomized, open-label study in patients with recurrent ovarian cancer. Etanercept was administered subcutaneously at a dose of 25 mg twice weekly (cohort one) and 25 mg thrice weekly (cohort two) until disease progression.

RESULTS

Thirty patients were recruited (cohort one, 17 patients; cohort two, 13 patients). Eighteen of the 30 patients (cohort one, 11 patients; cohort two, seven patients) completed > or = 12 weeks of treatment. Six patients achieved prolonged disease stabilization (cohort one, two patients [40 and 25 weeks]; cohort two, four patients [34, 24, 22, and 24 weeks]). A significant rise in immunoreactive TNF was seen in all patients (pretreatment compared with end of treatment). A phytohemagglutinin-stimulated whole-blood cytokine assay showed a significant fall in interleukin-6 (cohort one [11 of 17]) and CCL2 (cohort one [13 of 17]) levels. Common adverse effects were injection-site reactions and fatigue.

CONCLUSION

We provide evidence for the biologic activity and safety of etanercept in recurrent ovarian cancer. Our data suggest possible clinical activity that must be confirmed in future studies.

Phase I study of MetXia-P450 gene therapy and oral cyclophosphamide for patients with advanced breast cancer or melanoma

PURPOSE

MetXia-P450 is a novel recombinant retroviral vector that encodes the human cytochrome P450 type 2B6 gene (CYP2B6), Escherichia coli lacZ, and neomycin resistance marker genes. Cytochrome P450 enzymes are primarily expressed in the liver and convert the prodrug cyclophosphamide to an active phosphoramide mustard and acrolein. Gene-based delivery of CYP2B6 to the tumor site leads to local prodrug activation and higher concentrations of the active metabolites at the target site.

EXPERIMENTAL DESIGN

MetXia-P450 was directly injected into metastatic cutaneous tumor nodules on days 1 and 2 and nodules biopsied on day 7. Oral cyclophosphamide (100 mg/m(2)) was administered between days 8 and 22. Subsequent cycles of oral cyclophosphamide were repeated for 2 of 4 weeks. Gene transfer levels in biopsy samples were measured by histologic and quantitative PCR analyses. Safety assessments were made using PCR for vector dissemination to the blood after injection and using PCR and serologic analyses to detect replicating virus. Secondary end points included clinical response, toxicity, and evaluation of antitumor immune responses by measurement of carcinoembryonic antigen and 5T4 antibodies.

RESULTS

Twelve patients with breast cancer (n = 9) and melanoma (n = 3) received three dose levels of MetXia-P450 ( approximately 8 x 10(5), approximately 8 x 10(6), and approximately 8 x 10(7) lacZ transferring units/mL). The product was safe and well tolerated. The lacZ transgene was detected in biopsy material by immunohistochemistry in 10 of 12 patients and integrated viral sequences by PCR in 3 of 6 patients. One (8%) patient with breast cancer had a partial response and received 7 months of oral cyclophosphamide. Four (33%) patients had stable disease for > or =3 months and the rest had progressive disease. Preliminary immunologic analyses were suggestive of an antitumor response in two patients (partial response in one patient and stable disease in one patient).

CONCLUSION

MetXia was safe and well tolerated. Gene transfer was detected at all dose levels, and the initial suggestion of an antitumor response indicates that MetXia-P450 should undergo further clinical assessment.

A phase II study of etanercept (Enbrel), a tumor necrosis factor alpha inhibitor in patients with metastatic breast cancer

PURPOSE

Tumor necrosis factor (TNF) alpha is a key player in the tumor microenvironment and is involved in the pathogenesis of breast cancer. Etanercept is a recombinant human soluble p75 TNF receptor that binds to TNF-alpha and renders it biologically unavailable. In the current study, we sought to determine the toxicity, biological activity, and therapeutic efficacy of Etanercept in metastatic breast cancer.

EXPERIMENTAL DESIGN

We initiated a Phase II, nonrandomized, open-labeled study in patients with progressive metastatic breast cancer refractory to conventional therapy (Phase I toxicity data were available in patients with rheumatoid arthritis). Etanercept was administered subcutaneously at a dose of 25 mg twice weekly until disease progression.

RESULTS

Sixteen patients were recruited [median age 53 years (range, 34 to 74)]. A total of 141.6 weeks of therapy was administered (median of 8.1 weeks). Seven patients received > or =12 weeks of therapy. The most common side effects were injection site reactions (6), fatigue (5), loss of appetite (2), nausea (1), headache (1), and dizziness (1). Brief period of disease stabilization was seen in 1 patient lasting for 16.4 weeks. Immunoreactive TNF-alpha was elevated within 24 hours of therapy and persisted until the end of treatment (days 7, 28, 56, and 84). Phytohemagglutinin stimulates the production of interleukin-6 and CCL2 in peripheral blood cells, and the ability of Etanercept to modulate this response was assessed in a cytokine release assay. A consistent decrease in interleukin-6 and CCL2 level was seen compared with pretreatment values in serial blood samples (days 1, 7, 28, 56, and 84).

CONCLUSIONS

Our study shows the safety and biological activity of Etanercept in breast cancer and provides data to assess pharmacodynamic endpoints of different schedules of Etanercept and combinations with chemotherapy or other biological therapies.

Functional interaction between the Bloom's syndrome helicase and the RAD51 paralog, RAD51L3 (RAD51D)

Bloom's syndrome (BS) is a genetic disorder associated with short stature, fertility defects, and a predisposition to the development of cancer. BS cells are characterized by genomic instability; in particular, a high rate of reciprocal exchanges between sister-chromatids and homologous chromosomes. The BS gene product, BLM, is a helicase belonging to the highly conserved RecQ family. BLM is known to form a complex with the RAD51 recombinase, and to act upon DNA intermediates that form during homologous recombination, including D-loops and Holliday junctions. Here, we show that BLM also makes a direct physical association with the RAD51L3 protein (also known as RAD51D), a so-called RAD51 paralog that shows limited sequence similarity to RAD51 itself. This interaction is mediated through the N-terminal domain of BLM. To analyze functional interactions between BLM and RAD51L3, we have purified a heteromeric complex comprising RAD51L3 and a second RAD51 paralog, XRCC2. We show that the RAD51L3-XRCC2 complex stimulates BLM to disrupt synthetic 4-way junctions that model the Holliday junction. We also show that a truncated form of BLM, which retains helicase activity but is unable to bind RAD51L3, is not stimulated by the RAD51L3-XRCC2 complex. Our data indicate that the activity of BLM is modulated through an interaction with the RAD51L3-XRCC2 complex, and that this stimulatory effect on BLM is dependent upon a direct physical association between the BLM and RAD51L3 proteins. We propose that BLM co-operates with RAD51 paralogs during the late stages of homologous recombination processes that serve to restore productive DNA replication at sites of damaged or stalled replication forks.

Comparison of prognostic factors in patients in phase I trials of cytotoxic drugs vs new noncytotoxic agents

The aims of this study were to identify prognostic variables for toxicity and survival in patients with cancer participating in phase I clinical trials and compare characteristics of those treated with cytotoxic chemotherapy (CT) and non-cytotoxic drugs (non-CT). Data were collected from 420 (114 CT, 306 non-CT) patients enrolled in 16 phase I trials (five CT and 11 non-CT trials) in one cancer centre. Analyses of all patients were used to compare treatment groups, identify predictive variables for toxicity and to estimate prognostic factors in overall survival (OS). These were used to develop a prognostic index (PI). Multivariate analysis found those patients with better performance status, fewer sites of metastases, baseline Hb>12 g dl⁻¹ and WBC or LDH in the normal range had significantly better OS. Male gender, platelet count <450 × 10⁹ l⁻¹, high WBC or treatment with a non-CT phase I agent significantly reduced the chance of grade 3/4 toxicity. Overall survival was not significantly different between the CT and non-CT groups (260 vs 192 days, P=0.47) except for those with liver metastases (228 vs 137 days, P=0.02). Overall tumour response was 4.9% (95% CI: 2.7–7.0%). The PI identified three distinct patient groups with median survival of 321, 257 and 117 days. In conclusion, entry into a phase I trial of a non-CT drug is a safe option for heavily pretreated patients with cancer. The PI generated from these data can estimate the survival probability for patients entering phase I studies.

Pharmacokinetic study of cisplatin and infusional etoposide phosphate in advanced breast cancer with correlation of response to topoisomerase IIalpha expression

PURPOSE

There is substantial interpatient variability in etoposide pharmacokinetics. Pharmacokinetic adjustment to specific plasma concentrations may make it possible to define a therapeutic plasma concentration and relate drug target expression in the tumor to response. This study evaluated the combination of cisplatin with a prolonged infusion of etoposide phosphate (EP) in advanced breast cancer and correlated response to topoisomerase II expression.

EXPERIMENTAL DESIGN

Eligible patients, previously treated with an anthracycline, received 60 mg/m(2) cisplatin, followed by a 5-day infusion of EP. Plasma etoposide levels were measured on days 2 and 4 of each cycle with adjustment of the infusion rate to achieve an initial target etoposide concentration of 2 micro g/ml or 1.5 micro g/ml. Primary tumor blocks were stained by immunohistochemistry for topoisomerase IIalpha and beta.

RESULTS

Thirty-six patients, treated in three consecutive cohorts, received 145 cycles of chemotherapy. Targeting plasma etoposide concentration reduced interpatient pharmacokinetic variability (32% and 62% of patients, respectively, within 10% of target concentration on days 2 and 4; cycle 1). Significant hematological toxicity (89% of patients with at least one episode of grade III/IV neutropenia, 64% of patients with at least one episode of grade III/IV thrombocytopenia) was observed. Thirty-nine percent of patients achieved a partial response, and 19% had stable disease for at least 3 months. The median time to tumor progression was 4 months, with a median survival of 11 months. Topoisomerase IIalpha expression was significantly higher (P < 0.001) in responding patients compared with those with stable or progressive disease. There was no difference in topoisomerase IIbeta expression between groups.

CONCLUSION

Cisplatin and infusional EP is an active, but intensive, schedule in heavily pretreated patients with breast cancer. Clinical response correlates with tumor topoisomerase IIalpha expression.

Phase II study of exatecan mesylate (DX-8951f) as first line therapy for advanced non-small cell lung cancer

BACKGROUND

Exatecan mesylate (DX-8951f) is a water soluble analogue of camptothecin that inhibits topoisomerase I. This multi-centre phase II study evaluated the activity of single agent exatecan in previously untreated patients with advanced non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Patients with histologically or cytologically proven stage IIIb or IV NSCLC were treated with exatecan 0.5 mg/m(2) per day by 30 min intra-venous (i.v.) infusion for 5 days every 3 weeks to a maximum of six cycles. Measurable disease was documented prior to study entry and patients were re-staged every two cycles. Pharmacokinetic (PK) sampling was performed during cycle one.

RESULTS

39 patients (32 patients ECOG performance status 0 or 1; 29 male and ten female; mean age 63 years) were entered into the study. Thirty-three completed at least two cycles of exatecan and 11 completed six cycles. Two patients (5.1%, 95% C.I. 0.3-21.3%) had a partial response, 7 (18.0%) minor response and 8 (20.5%) stable disease. Median time to tumour progression (TTP) was 88 days and median overall survival 262 days. The main toxicity was reversible neutropenia. PK analysis of exatecan demonstrated a mean clearance of 2.28 l/h per m(2), volume of distribution 18.2 l/m(2) and mean elimination half-life of 7.9 h.

CONCLUSIONS

Exatecan mesylate has limited activity in advanced NSCLC and is not recommended for further evaluation as a single agent in this tumour type. PK data from this trial supports results established in phase I studies.

Phase I and pharmacokinetic study of the topoisomerase I inhibitor, exatecan mesylate (DX-8951f), using a weekly 30-minute intravenous infusion, in patients with advanced solid malignancies

BACKGROUND

The topoisomerase I inhibitor exatecan mesylate (DX-8951f ) is a water-soluble hexacyclic analogue of camptothecin that does not require enzymatic activation. This study determined the toxicity, maximum tolerated dose (MTD), pharmacokinetics and pharmacodynamics of a weekly intravenous (i.v.) schedule of DX-8951f.

PATIENTS AND METHODS

Thirty-five patients with advanced solid malignancies, stratified as minimally (MP) or heavily (HP) pre-treated, received escalating doses of DX-8951f as 30-min i.v. infusions for three out of every 4 weeks. Pharmacokinetics were described after the first infusion of DX-8951f.

RESULTS

Infusions (244) of DX-8951f were administered with a median of two cycles (range 1-10). The main toxicity observed was haematological. There was no significant gastrointestinal toxicity. Two patients (6%) had confirmed partial responses. Twelve patients (39%) had stable disease. DX-8951f had a terminal elimination half-life of approximately 8 h and a clearance of 2 l/h/m(2). The area under the plasma concentration versus time curve (AUC( infinity )) and the maximum plasma concentration (C(max)) increased linearly with the dose. A linear relationship was present for the percentage decrease in neutrophil counts or platelet counts and AUC( infinity ) as well as C(max).

CONCLUSIONS

The dose-limiting toxicity of DX-8951f is neutropenia for MP patients and neutropenia and thrombocytopenia for HP patients. Evidence for clinical activity was seen, suggesting phase II study of the drug is indicated. Using this schedule the recommended dose is 2.75 mg/m(2)/week for MP patients and 2.10 mg/m(2)/week for HP patients.

Low-dose IFN-gamma induces tumor MHC expression in metastatic malignant melanoma

Specific antitumor immune responses require expression of MHC class I or II molecules on tumor cells, and MHC antigen down-regulation is a presumed tumor growth promoting mechanism. Because IFN-gamma up-regulates tumor MHC antigen expression in vitro, in this Phase II trial of an immunologically active dose and schedule we evaluated whether this was the case in vivo. Twenty-three patients with metastatic melanoma were treated with IFN-gamma 100 microg/m(2) s.c. once weekly for a maximum of 6 months. There were three complete responses, now maintained for 53, 36, and 25 months. The remainder had progressive disease. The treatment was well tolerated, with no toxicity exceeding National Cancer Institute Common Toxicity Criteria grade II. Immunohistochemical analysis of tumor biopsies during treatment was performed using monoclonal antibodies to HLA class I (W/632) and class II (CR3/43) monomorphic determinants. HLA class I was down-regulated in 2 of 19 patients pretreatment and up-regulated by IFN-gamma in both. HLA class II was down-regulated pretreatment in 14 of 18 patients and up-regulated by IFN-gamma in 6 (43%). The HLA up-regulation persisted throughout the study. IFN-gamma induced significant but short-lived up-regulation of surrogate markers of monocyte activation (serum neopterin) and class I up-regulation (serum beta-2-microglobulin) in most patients. There was no consistent relationship between surrogate marker up-regulation, tumor antigen up-regulation, and responses. The study shows that the significant immune modulation induced by IFN-gamma does not correlate with tumor responses and that the serum surrogate marker changes do not reflect tumor events. The durable and long-lived responses, clear demonstration of tumor MHC up-regulation, and low toxicity suggest that weekly IFN-gamma 100 microg/m(2) would be a useful addition to chemoimmunotherapeutic regimens.

Phase I and pharmacokinetic study of PKC412, an inhibitor of protein kinase C

PURPOSE

N-Benzoyl staurosporine (PKC412) is a protein kinase C inhibitor with antitumor activity in laboratory models. We determined the toxicity of oral PKC412 administered daily for repeat cycles of 28 days.

PATIENTS AND METHODS

Thirty-two patients with advanced solid cancers were treated at seven dose levels (12.5 to 300 mg daily) for a total of 68 cycles.

RESULTS

The most frequent treatment-related toxicities were nausea, vomiting, fatigue, and diarrhea. At the two top dose levels (225 and 300 mg/d), 15 of 16 patients experienced nausea/vomiting (common toxicity criteria [CTC], version 1), grade 2 in nine of 16 and grade 3 in three of 16 patients; and six of 16 patients developed CTC grade 2 diarrhea. After 1 month of treatment, there were significant reductions in circulating lymphocyte (P <.02) and monocyte (P <.01) counts in patients receiving doses > or = 100 mg/d. Nevertheless, only two patients developed myelosuppression (both grade 2). Of two patients with progressive cholangiocarcinoma, one attained stable disease lasting 4.5 months and one a partial response lasting 4 months. There was a linear relationship between PKC412 dose and area under the curve (0-24 hours) and maximum plasma concentration with marked interpatient variability. The estimated median elimination half-life was 1.6 days (range, 0.9 to 4.0 days), and a metabolite with a median half-life of 36 days was detected. Steady-state PKC412 plasma levels at the top three dose cohorts (150 to 300 mg) were five to 10 times the cellular 50% inhibitory concentration for PKC412 of 0.2 to 0.7 micromol/L.

CONCLUSION

PKC412 can be safely administered by chronic oral therapy, and 150 mg/d is suitable for phase II studies. The pharmacokinetics and lack of conventional toxicity indicate that pharmacodynamic measures may be additionally needed to optimize the drug dose and schedule.

A phase II study of razoxane, an antiangiogenic topoisomerase II inhibitor, in renal cell cancer with assessment of potential surrogate markers of angiogenesis

Renal cell carcinoma (RCC) is an angiogenic tumor resistant to standard cytotoxic chemotherapeutic agents. Although often responsive to immunomodulatory agents including interleukin 2 and IFN-alpha, the overall results in randomized Phase III studies are disappointing with only modest improvements in overall survival. This Phase II study evaluated the efficacy and tolerability of razoxane, an antiangiogenic topoisomerase II inhibitor, in 40 patients (32 men, 8 women; age: range, 31-76 years; median, 58 years) with inoperable RCC. Twenty patients received razoxane 125 mg p.o., twice a day for 5 days each week for 8 weeks (one cycle). This was repeated in patients with stable disease (StD), but was discontinued after 16 weeks if there was no evidence of an objective response. Because minimal toxicity was seen, subsequent patients (n = 20) were treated until progressive disease (PD) was documented. Of 38 evaluable patients, 11 (29%) had StD for a minimum of 4 months, and the remainder had PD. Median overall survival was 7.3 months. Duration of survival was significantly better in patients with StD compared with those with PD (P = 0.003). The effect of treatment on six potential surrogate serum/plasma (vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), urokinase plasminogen activator soluble receptor (uPAsr), E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and von Willebrand's factor (vWF) and two urinary (VEGF and bFGF) markers of angiogenesis was evaluated before and after 1 cycle of treatment. Pretreatment serum VEGF and E-selectin levels above the median value were associated with a poor prognosis. Serum VCAM-1 levels and urinary VEGF levels rose significantly after one cycle in patients with PD but not in those with StD. Serum VEGF, bFGF, VCAM-1 and vWF, plasma uPAsr and urinary bFGF levels were significantly higher in PD patients compared with StD patients before and/or after 1 cycle of treatment. In conclusion, razoxane is an antiangiogenic agent that has minimal toxicity and that requires further evaluation in combination with other active agents in the treatment of RCC. Surrogate serum and urinary markers of angiogenesis may have a role to play in predicting disease response and overall survival in RCC.

The RAD51 family member, RAD51L3, is a DNA-stimulated ATPase that forms a complex with XRCC2

The Rad51 protein in eukaryotic cells is a structural and functional homolog of Escherichia coli RecA with a role in DNA repair and genetic recombination. Several proteins showing sequence similarity to Rad51 have previously been identified in both yeast and human cells. In Saccharomyces cerevisiae, two of these proteins, Rad55p and Rad57p, form a heterodimer that can stimulate Rad51-mediated DNA strand exchange. Here, we report the purification of one of the representatives of the RAD51 family in human cells. We demonstrate that the purified RAD51L3 protein possesses single-stranded DNA binding activity and DNA-stimulated ATPase activity, consistent with the presence of "Walker box" motifs in the deduced RAD51L3 sequence. We have identified a protein complex in human cells containing RAD51L3 and a second RAD51 family member, XRCC2. By using purified proteins, we demonstrate that the interaction between RAD51L3 and XRCC2 is direct. Given the requirements for XRCC2 in genetic recombination and protection against DNA-damaging agents, we suggest that the complex of RAD51L3 and XRCC2 is likely to be important for these functions in human cells.

Evaluation of toremifene for reversal of multidrug resistance in renal cell cancer patients treated with vinblastine

PURPOSE

Expression of P-glycoprotein (Pgp), which confers the multidrug resistance (MDR) phenotype, is thought to contribute to the insensitivity of renal cell cancer (RCC) to chemotherapy. The development of Pgp inhibitors for clinical application has been hampered by unacceptable toxicity at doses required to achieve adequate cellular concentration. Toremifene is able to reverse MDR and sensitise RCC to vinblastine in vitro. However, in vivo toremifene is tightly bound to serum proteins, in particular the acute phase protein alpha1-acid glycoprotein (AAG), which may limit tissue availability. In this phase I-II study we assessed the tolerability of short courses of high dose toremifene in combination with vinblastine and evaluated the key determinants of MDR reversal in vivo.

METHODS

Twenty-seven patients with metastatic RCC received escalating doses of oral toremifene for 3 days every 2 weeks in combination with vinblastine 6 mg/m2 i.v. on day 3 of each cycle. The serum concentration of toremifene, its metabolites and AAG were measured and the effect of patients' serum on inhibition of Pgp in vitro was determined.

RESULTS

Twenty-six patients were evaluable for response. Eight patients (31%) had stable disease and 18 patients (69%) progressive disease. The mean serum concentration of toremifene at 780 mg daily for 3 days was 7.82 microM [standard deviation (SD) 2.48, range 2.50 to 14.70], which exceeds that known to reverse MDR in vitro. The serum concentration of the major metabolite of toremifene, N-demethyltoremifene, which also reverses MDR, was 5.13 microM (SD 1.78, range 1.80 to 9.00). In 60% of patients the pre-treatment AAG concentration was above that known to block the effects of toremifene in vitro. However, addition of serum from patients on toremifene to MCF-7 adr cells in vitro inhibited Pgp-mediated efflux of rhodamine 123.

CONCLUSIONS

We have shown that short course, high-dose toremifene in combination with vinblastine is generally well tolerated and that the concentration of toremifene required to reverse MDR in vitro is achievable in vivo.

Induction of thymidine phosphorylase as a pharmacodynamic end-point in patients with advanced carcinoma treated with 5-fluorouracil, folinic acid and interferon alpha

Thymidine phosphorylase (TP) is an essential enzyme for the biochemical activation of 5-fluorouracil (5-FU). Interferon upregulates TP in vivo, although the dose and schedule of interferon for optimal biomodulation of 5-FU is not known. In this study, TP activity was measured in peripheral blood lymphocytes (PBLs) from patients with advanced carcinoma receiving treatment with 5-FU and folinic acid. Cohorts of patients were treated with interferon alpha (IFNalpha), immediately prior to 5-FU/folinic acid, at doses of 3 MIU m(-2), 9 MIU m(-2) and 18 MIUm(-2). IFNalpha was administered on day 0 cycle two, day-1 and day 0 cycle three and day-2, day-1 and day 0 cycle four. A fourth cohort was treated with IFNalpha 9 MIU m(-2) three times per week from cycle 2 onwards. Twenty-one patients were entered into the study with 19 evaluable for response. Six patients (32%) had stable disease and 13 (68%) progressive disease. There were no grade-IV toxicities. TP activity was detected in PBLs from all patients with wide interpatient variability in constitutive TP activity prior to chemotherapy, and in response to IFNalpha. 5-FU/folinic acid alone did not induce TP activity but a single dose of IFNalpha led to upregulation of TP within 2 h of administration with a further increase by 24 h (signed rank test, P = 0.006). TP activity remained elevated for at least 13 days (signed rank test, P= 0.02). There were no significant differences in TP activity between schedules or with additional doses of IFNalpha. A single dose of IFNalpha as low as 3 MIU m(-2) can cause sustained elevation of PBL TP activity in vivo indicating that biochemical markers are important pharmacodynamic endpoints for developing optimal schedules of IFNalpha for biomodulation of 5-FU.

Phase II study of the oxygen saturation curve left shifting agent BW12C in combination with the hypoxia activated drug mitomycin C in advanced colorectal cancer

BW12C (5-[2-formyl-3-hydroxypenoxyl] pentanoic acid) stabilizes oxyhaemoglobin, causing a reversible left-shift of the oxygen saturation curve (OSC) and tissue hypoxia. The activity of mitomycin C (MMC) is enhanced by hypoxia. In this phase II study, 17 patients with metastatic colorectal cancer resistant to 5-fluorouracil (5-FU) received BW12C and MMC. BW12C was given as a bolus loading dose of 45 mg kg(-1) over 1 h, followed by a maintenance infusion of 4 mg kg(-1) h(-1) for 5 h. MMC 6 mg m(-2) was administered over 15 min immediately after the BW12C bolus. The 15 evaluable patients had progressive disease after a median of 2 (range 1-4) cycles of chemotherapy. Haemoglobin electrophoresis 3 and 5 h after the BW12C bolus dose showed a fast moving band consistent with the BW12C-oxyhaemoglobin complex, accounting for approximately 50% of total haemoglobin. The predominant toxicities--nausea/vomiting and vein pain--were mild and did not exceed CTC grade 2. Liver 31P magnetic resonance spectroscopy of patients with hepatic metastases showed no changes consistent with tissue hypoxia. The principle of combining a hypoxically activated drug with an agent that increases tissue hypoxia is clinically feasible, producing an effect equivalent to reducing tumour oxygen delivery by at least 50%. However, BW12C in combination with MMC for 5-FU-resistant colorectal cancer is not an effective regimen. This could be related to drug resistance rather than a failure to enhance cytotoxicity.

Phase II study of second-line therapy with DTIC, BCNU, cisplatin and tamoxifen (Dartmouth regimen) chemotherapy in patients with malignant melanoma previously treated with dacarbazine

This study assessed response rates to combination dacarbazine (DTIC), BCNU (carmustine), cisplatin and tamoxifen (DBPT) chemotherapy in patients with progressive metastatic melanoma previously treated with DTIC, as an evaluation of DBPT as a second-line regimen, and as an indirect comparison of DBPT with DTIC. Thirty-five consecutive patients received DBPT. The patients were divided into two groups. Group 1 comprised 17 patients with progressive disease (PD) on DTIC + tamoxifen therapy who were switched directly to DBPT. Group 2 comprised 18 patients not immediately switched to DBPT and included patients who had either a partial response (PR; one patient) or developed stable disease (SD; four patients) with DTIC, or received adjuvant DTIC (nine patients). All except four patients had received tamoxifen at the time of initial DTIC treatment. Median times since stopping DTIC were 22 days (range 20-41) and 285 days (range 50-1,240) in Groups 1 and 2 respectively. In Group 1, one patient developed SD for 5 months and the remainder had PD. In Group 2, there were two PRs, four patients with SD (4, 5, 6, and 6 months), and 11 with PD. These results indicate that the DBPT regimen is not of value in melanoma primarily refractory to DTIC. There were responses in patients not directly switched from DTIC to DBPT, suggesting combination therapy may be of value in a small subgroup of melanoma patients.

Evaluation of the alkaline comet assay and urinary 3-methyladenine excretion for monitoring DNA damage in melanoma patients treated with dacarbazine and tamoxifen

PURPOSE

To develop, using dacarbazine as a model, reliable techniques for measuring DNA damage and repair as pharmacodynamic endpoints for patients receiving chemotherapy.

METHODS

A group of 39 patients with malignant melanoma were treated with dacarbazine 1 g/m(2) i.v. every 21 days. Tamoxifen 20 mg daily was commenced 24 h after the first infusion and continued until 3 weeks after the last cycle of chemotherapy. DNA strand breaks formed during dacarbazine-induced DNA damage and repair were measured in individual cells by the alkaline comet assay. DNA methyl adducts were quantified by measuring urinary 3-methyladenine (3-MeA) excretion using immunoaffinity ELISA. Venous blood was taken on cycles 1 and 2 for separation of peripheral blood lymphocytes (PBLs) for measurement of DNA strand breaks.

RESULTS

Wide interpatient variation in PBL DNA strand breaks occurred following chemotherapy, with a peak at 4 h (median 26.6 h, interquartile range 14.75-40.5 h) and incomplete repair by 24 h. Similarly, there was a range of 3-MeA excretion with peak levels 4-10 h after chemotherapy (median 33 nmol/h, interquartile range 20.4-48.65 nmol/h). Peak 3-MeA excretion was positively correlated with DNA strand breaks at 4 h (Spearman's correlation coefficient, r=0.39, P=0.036) and 24 h (r=0.46, P=0.01). Drug-induced emesis correlated with PBL DNA strand breaks (Mann Whitney U-test, P=0.03) but not with peak 3-MeA excretion.

CONCLUSIONS

DNA damage and repair following cytotoxic chemotherapy can be measured in vivo by the alkaline comet assay and by urinary 3-MeA excretion in patients receiving chemotherapy.

Phase I trial of the selective mitochondrial toxin MKT077 in chemo-resistant solid tumours

BACKGROUND

MKT077 is a rhodacyanine dye analogue which preferentially accumulates in tumour cell mitochondria. It is cytotoxic to a range of tumours. In this phase I study, MKT077 was administered as a five-day infusion once every three weeks.

PATIENTS AND METHODS

Ten patients, median age 59 (38-70) years, with advanced solid cancers were treated at three dose levels: 30, 40 and 50 mg/m2/day for a total of 18 cycles. 31Phosphorus magnetic resonance spectroscopy (MRS) was used to evaluate the effect of MKT077 on skeletal muscle mitochondrial function.

RESULTS

The predominant toxicity was recurrent reversible functional renal impairment (grade 2, two patients). One patient with renal cancer attained stable disease and the remainder progressive disease. There were no MRS changes in the first or second treatment cycles but one patient received 11 treatment cycles and developed changes consistent with a mitochondrial myopathy. Mean values for all pharmacokinetic parameters were at sub micromolar levels and did not exceed IC50 values (> or = 1 microM).

CONCLUSIONS

Because of the renal toxicity, and animal studies showing MKT077 causes eventual irreversible renal toxicity, further recruitment was halted. The study shows, however, that it is feasible to target mitochondria with rhodacyanine analogues, if drugs with higher therapeutic indices could be developed.

A phase II study of the modulation of 5-fluorouracil and folinic acid with high-dose infusional hydroxyurea in metastatic colorectal carcinoma

BACKGROUND

Hydroxyurea (HU), an inhibitor of ribonucleotide reductase, may potentiate the activity of 5-fluorouracil (5-FU) and folinic acid (FA) by reducing the deoxyribonucleotide pool available for DNA synthesis and repair. However as HU may inhibit the formation of 5-fluoro-2-deoxyuridine-5-monophosphate (FdUMP), one of the principal active metabolites of 5-FU, the scheduling of HU may be critical. In vitro experiments suggest that administration of HU following 5-FU, maintaining the concentration in the region of 1 mM for six or more hours, significantly enhances the efficacy of 5-FU.

PATIENTS AND METHODS

5-FU/FA was given as follows: days 1 and 2-FA 250 mg/m2 (max. 350 mg) over two hours followed by 5-FU 400 mg/m2 by intravenous bolus (i.v.b.) over 15 minutes and subsequently 5-FU 400 mg/m2 infusion (ivi) over 22 hours. HU was administered on day 3 immediately after the 5-FU with 3 g i.v.b. over 15 minutes followed by 12 g ivi over 12 hours.

RESULTS

Thirty patients were entered into the study. Median survival was nine months (range 1-51+ months). There were eight partial responses (28%, 95% CI: 13%-47%). The median duration of response was 6.5 (range 4-9 months). Grade 3-4 toxicities included neutropenia (grade 3 in eight patients and grade 4 in five), anaemia (grade 3 in one patient) and diarrhoea (grade 3 in two patients). Neutropenia was associated with pyrexia in two patients. Phlebitis at the infusion site occurred in five patients. The treatment was complicated by pulmonary embolism in one patient and deep venous thrombosis in another.

CONCLUSION

HU administered in this schedule is well tolerated. Based on these results and those of other phase II studies, a randomised phase III study of 5-FU, FA and HU versus 5-FU and FA using the standard de Gramont schedule is recommended.

Phase I study of the novel cyclic AMP (cAMP) analogue 8-chloro-cAMP in patients with cancer: toxicity, hormonal, and immunological effects

The cyclic AMP (cAMP)-dependent protein kinase regulatory subunit RI is overexpressed in cancer cells. 8-Chloro-cAMP (8-Cl-cAMP) is an RII site-specific analogue that down-regulates RI and inhibits the growth of a wide range of cancer cells in vitro and in vivo. We performed a Phase I trial of 8-Cl-cAMP in 32 patients with malignancies that were refractory to standard treatments. 8-Cl-cAMP was initially given in a 1-month cycle by constant infusion at 0.005 mg/kg/h for 21 days, followed by 1 week of rest. The dose was escalated to 0.045 mg/kg/h, but hypercalcemia became the dose-limiting toxicity. The length of drug administration was, therefore, reduced to 5 days per week for the first 3 weeks of the cycle, but it was not possible to increase the drug dose without producing hypercalcemia. Hence, the length of drug administration was reduced to 3 days per week for the first 3 weeks of the cycle. The maximum tolerated dose for this regimen was 0.15 mg/kg/h, and the dose-limiting toxicities were reversible hypercalcemia and hepatotoxicity. Stable disease for > or =4 months was observed in two patients treated at > or =0.045 mg/kg. cAMP-dependent protein kinase is involved in hormone- and cytokine-mediated signaling, and so representative hormone, cytokine, and peripheral lymphocyte subsets were measured. The drug had a parathyroid hormone-like effect on calcium homeostasis and significantly increased circulating luteinizing hormone and 17-hydoxyprogesterone levels (P < 0.02 and P < 0.0006, respectively). We conclude that 8-Cl-cAMP is well tolerated without attendant myelotoxicity, and in this study, it was associated with biological effects. In Phase II studies, a dose of 0.11 mg/kg/h for 3 days per week would be appropriate.

Phase II study of RC-160 (vapreotide), an octapeptide analogue of somatostatin, in the treatment of metastatic breast cancer

RC-160 (octastatin/vapreotide) is a potent octapeptide analogue of somatostatin with growth inhibitory activity in experimental tumours in vitro and in vivo, including breast cancer. We evaluated the efficacy and tolerability of high-dose RC-160, 3 mg day(-1) on week 1 increased to 4.5 mg day(-1) for weeks 2-4 and subsequently 6 mg day(-1) until the end of treatment, administered by continuous subcutaneous infusion in the management of 14 women with previously treated metastatic breast cancer. The age range was 37-80 years (median 58.5 years) and performance status 0-2. The treatment was well tolerated with no dose reductions being required. No grade 3 or 4 toxicities were seen. Abscess formation developed at the infusion site in eight patients and erythema and discomfort was seen in a further three patients. A significant reduction in IGF-I levels occurred by day 7 and was maintained throughout the treatment. The lowest dose of RC-160 produced the maximal IGF-I response. Although there was no reduction in prolactin levels in patients whose baseline levels were normal, elevated prolactin levels found in three patients fell to within the normal range 7 days after commencing RC-160 treatment. A small but significant rise in fasting blood glucose levels was also recorded, the highest level on treatment being 7.6 mmol l(-1). No objective tumour responses were observed, all patients showing disease progression within 3 months of commencing treatment. These findings demonstrate that high-dose RC-160, administered as a continuous subcutaneous infusion, can reduce serum levels of the breast growth factors IGF-I and prolactin but is ineffective in the management of metastatic breast cancer. Encouraging preclinical anti-tumour activity and the favourable toxicity profile in patients suggest the merit of future studies combining RC-160 with anti-oestrogen, cytotoxic and anti-angiogenic agents.

Phase I study of intrapleural batimastat (BB-94), a matrix metalloproteinase inhibitor, in the treatment of malignant pleural effusions

Tumor cells and associated stromal cells secrete matrix metalloproteinases (MMPs), contributing to invasion, angiogenesis, and metastasis. Batimastat (BB-94) is a broad-spectrum MMP inhibitor that causes resolution of ascites and/or tumor growth delay in animal models of breast, ovarian, and colorectal cancer. We recruited 18 patients with cytologically positive malignant pleural effusions into a Phase I study of intrapleural BB-94. Three patients received single doses of BB-94 at each dose level: 15, 30, 60, 105, 135, and 300 mg/m2. Two patients were retreated with a second course at 60 and 105 mg/m2. BB-94 was detectable in plasma 1 h after intrapleural administration, and peak levels of 20-200 ng/ml occurred after 4 h to 1 week. BB-94 persisted in the plasma for up to 12 weeks, at levels exceeding the IC50s for target MMPs. Peak values were higher, and persistence in the plasma was longer after higher doses of BB-94. The treatment was well tolerated. Toxic effects included low-grade fever for 24-48 h (6 of 18 patients, 33%) and reversible asymptomatic elevation of liver enzymes (8 patients, 44%). Toxicity seemed unrelated to BB-94 dose or plasma levels. Sixteen patients evaluable for response required significantly fewer pleural aspirations in the 3 months after BB-94 compared with the 3 months before. Seven patients (44%) required no further pleural aspiration until death/last follow-up. After 1 month, patients treated with 60-300 mg/m2 BB-94 had significantly better dyspnea scores, indicating improved exercise tolerance, compared with baseline scores the day after BB-94. The maximum tolerated intrapleural dose remains to be defined, but it is clear that intrapleural BB-94 is well tolerated, with evidence of local activity.

A phase II study of bryostatin 1 in metastatic malignant melanoma

Bryostatin 1 is a protein kinase C partial agonist which has both antineoplastic and immune-stimulatory properties, including the induction of cytokine release and expansion of tumour-specific lymphocyte populations. In phase I studies, tumour responses have been observed in patients with malignant melanoma, lymphoma and ovarian carcinoma. The dose-limiting toxicity is myalgia. Sixteen patients (age 35-76 years, median 57 years) with malignant melanoma were treated. All had received prior chemotherapy. In each cycle of treatment, patients received bryostatin 25 degrees g m(-2) weekly for three courses followed by a rest week. The drug was given in PET diluent (10 microg bryostatin ml(-1) of 60% polyethylene glycol, 30% ethanol, 10% Tween 80) and infused in normal saline over 1 h. The principal toxicities were myalgia (grade 2, eight patients and grade 3, six patients) and grade 2 phlebitis (four patients), fatigue (three patients) and vomiting (one patient). Of 15 patients evaluable for tumour response, 14 developed progressive disease. One patient developed stable disease for 9 months after bryostatin treatment. In conclusion, single-agent bryostatin appears ineffective in the treatment of metastatic melanoma in patients previously treated with chemotherapy. It should, however, be investigated further in previously untreated patients.

A phase II study of mitomycin C and oral etoposide for advanced adenocarcinoma of the upper gastrointestinal tract

BACKGROUND

Mitomycin C and etoposide have both demonstrated activity against gastric carcinoma. Etoposide is a topoisomerase II inhibitor with evidence for phase-specific and schedule-dependent activity.

PATIENTS AND METHOD

Twenty-eight consecutive patients with advanced upper gastrointestinal adenocarcinoma were treated with intravenous (i.v.) bolus mitomycin C 6 mg/m2 on day 1 every 21 days to a maximum of four courses. Oral etoposide capsules 50 mg b.i.d. (or 35 mg b.i.d. liquid) were administered days 1 to 10 extending to 14 days in subsequent courses if absolute neutrophil count > 1.5 x 10(9)/l on day 14 of first course, for up to six courses.

RESULTS

Twenty-six patients were assessed for response of whom 12 had measurable disease and 14 evaluable disease. Four patients had a documented response (one complete remission, three partial remissions) with an objective response rate of 15% (95% confidence interval (95% CI) 4%-35%). Eight patients had stable disease and 14 progressive disease. The median survival was six months. The schedule was well tolerated with no treatment-related deaths. Nine patients experienced leucopenia (seven grade II and two grade III). Nausea and vomiting (eight grade II, one grade III), fatigue (eight grade II, two grade III) and anaemia (seven grade II, two grade III) were the predominant toxicities.

CONCLUSION

This out-patient schedule is well tolerated and shows modest activity in the treatment of advanced upper gastrointestinal adenocarcinoma. Further studies using protracted schedules of etoposide both orally and as infusional treatment should be developed.