A randomized, double-blind, placebo-controlled phase II study of maintenance therapy with tasquinimod in patients with metastatic castration-resistant prostate cancer responsive to or stabilized during first-line docetaxel chemotherapy

BACKGROUND

This phase II study was conducted to assess clinical efficacy of tasquinimod maintenance therapy in patients with metastatic castrate-resistant prostate cancer not progressing during first-line docetaxel-based therapy.

PATIENTS AND METHODS

Patients were randomly assigned (1 : 1) to receive tasquinimod (0.25-1.0 mg/day orally) or placebo. The primary end point was radiologic progression-free survival (rPFS); secondary efficacy end points included: overall survival (OS); PFS on next-line therapy (PFS 2) and symptomatic PFS, assessed using the Brief Pain Inventory (BPI) questionnaire and analgesic use. Quality of life was measured by the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire and by the EuroQol-5 Dimension Quality of Life Instrument (EQ-5D). Adverse events were recorded.

RESULTS

A total of 219 patients were screened and 144 patients randomized. The median duration of treatment was 18.7 weeks (range 0.6-102.7 weeks) for the tasquinimod arm and 19.2 weeks (range 0.4-80.0 weeks) for the placebo arm. Median (90% CI) rPFS was 31.7 (24.3-53.7) and 22.7 (16.1-25.9) weeks in the tasquinimod and placebo arms, respectively [HR (90% CI) 0.6 (0.4-0.9), P = 0.0162]. The median OS was not reached because only 14 deaths occurred by the cut-off date. No statistically significant differences between treatment arms were noted for symptomatic PFS, PFS 2, BPI score, FACT-P score, or EQ-5D. The incidence of any treatment emergent adverse event (TEAE) was similar in the tasquinimod and placebo arms (97.2% versus 94.3%, respectively), whereas severe TEAEs (NCI-CTC Grade 3-5) incidence was higher in the tasquinimod group (50.7% versus 27.1%).

CONCLUSIONS

Randomized trials testing new drugs as maintenance can be successfully conducted after chemotherapy in castrate-resistant prostate cancer. Maintenance tasquinimod therapy significantly reduced the risk of rPFS by 40%.

CLINICALTRIALS

gov identifier NCT01732549.

Phase I study of pulsatile 3-day administration of afatinib (BIBW 2992) in combination with docetaxel in advanced solid tumors

BACKGROUND

A phase I study to assess the maximum tolerated dose (MTD) of a short course of afatinib in combination with docetaxel for the treatment of solid tumors.

METHODS

Patients with advanced solid malignancies received docetaxel 75 mg/m(2) intravenously on day 1 and oral afatinib once daily on days 2-4, in 3-week treatment cycles. The afatinib dose was escalated in successive cohorts of 3-6 patients until dose-limiting toxicity (DLT). The MTD cohort was expanded to 13 patients. Pharmacokinetic parameters were assessed.

RESULTS

Forty patients were treated. Afatinib doses were escalated to 160 mg/day in combination with 75 mg/m(2) docetaxel. Three patients had drug-related DLTs during cycle 1. The MTD was defined as 90 mg/day afatinib (days 2-4) with docetaxel 75 mg/m(2). The most frequent drug-related adverse events (all grades) were alopecia, diarrhea, stomatitis (all 50 %) and rash (40 %, all grade ≤ 2). Three patients had confirmed responses, two patients had unconfirmed responses and nine patients had durable stable disease >6 cycles. No pharmacokinetic interaction was observed.

CONCLUSION

Afatinib 90 mg administered for 3 days after docetaxel 75 mg/m(2) is the MTD for this treatment schedule and the recommended phase II/phase III dose. This combination showed anti-tumor activity in phase I, with a manageable adverse-event profile.

Concomitant oral tyrosine kinase inhibitors and bisphosphonates in advanced renal cell carcinoma with bone metastases

BACKGROUND

The presence of bone metastases in patients with metastatic renal cell carcinoma treated with oral tyrosine kinase inhibitors (TKIs) is associated with poorer outcome as compared with patients without bone involvement. Concomitant bisphosphonates could probably improve outcomes but also induce osteonecrosis of the jaw (ONJ).

METHODS

Retrospective study on all the renal cell carcinoma patients with bone metastases treated with sunitinib or sorafenib between November 2005 and June 2012 at the University Hospitals Leuven and AZ Groeninge in Kortrijk.

RESULTS

Seventy-six patients were included in the outcome analysis: 49 treated with concomitant bisphosphonates, 27 with TKI alone. Both groups were well balanced in terms of prognostic and predictive markers. Response rate (38% vs 16% partial responses, P=0.028), median progression-free survival (7.0 vs 4.0 months, P=0.0011) and median overall survival (17.0 vs 7.0 months, P=0.022) were significantly better in patients receiving bisphosphonates. The incidence of ONJ was 10% in patients treated with TKI and bisphosphonates.

CONCLUSION

Concomitant use of bisphosphonates and TKI in renal cell carcinoma patients with bone involvement probably improves treatment efficacy, to be confirmed by prospective studies, but is associated with a high incidence of ONJ.

Phase I safety and pharmacokinetic study of SU-014813 in combination with docetaxel in patients with advanced solid tumours

BACKGROUND

In pre-clinical models enhanced anti-tumour activity was observed when SU-014813, an oral multi-targeted tyrosine kinase inhibitor was combined with docetaxel. This synergy might be explained by improvement of the penetration of cytotoxic agents into tumours as a result of both VEGFR and PDGFR inhibition. We assessed the maximal tolerated dose (MTD), evaluated the pharmacokinetics and preliminary anti-tumour efficacy of oral SU-014813 administered continuously in combination with docetaxel to patients with advanced solid tumours.

METHODS

In this phase I study successive patient cohorts received docetaxel 60 or 75mg/m(2) every 3weeks in combination with chronic daily dosing of SU-014813. Dose limiting toxicity was assessed both in the first and second treatment cycle.

RESULTS

Twenty-five patients were entered on study of which 24 started treatment. Dose limiting toxicities were prolonged neutropenia, neutropenic fever, fatigue and diarrhoea. Other toxicities included fatigue, alopecia, nausea, vomiting, anorexia, rash, hypertension and hair discolouration. The recommended phase II dose was determined to be docetaxel 75mg/m(2) in combination with SU-014813 50mg/day. There was no clinically relevant pharmacokinetic drug-drug interaction. Two patients (8%) achieved a partial response (PR) and 7 patients (29%) had stabilisation of their disease (SD) >6months, for a clinical benefit rate of 37.5%. The activity observed in patients with melanoma and sunitinib refractory gastrointestinal stromal tumours (GIST) was particularly noteworthy.

CONCLUSIONS

Oral SU-014813 50mg/day with docetaxel 75mg/m(2) is a clinically feasible regimen with a manageable safety profile and anti-tumour activity. Further development is warranted in patients with melanoma and GIST.

A randomized phase III study comparing standard dose BEP with sequential high-dose cisplatin, etoposide, and ifosfamide (VIP) plus stem-cell support in males with poor-prognosis germ-cell cancer. An intergroup study of EORTC, GTCSG, and Grupo Germinal (EORTC 30974)

BACKGROUND

To compare the efficacy of one cycle of standard dose cisplatin, etoposide, and ifosfamide (VIP) plus three cycles of high-dose VIP followed by stem-cell infusion [high-dose chemotherapy (HD-CT arm)] to four cycles of standard cisplatin, etoposide, and bleomycin (BEP) in patients with poor-prognosis germ-cell cancer (GCC).

PATIENT AND METHODS

Patients with poor-prognosis GCC were assigned to receive either BEP or VIP followed by HD-CT. To show a 15% improvement in a 1-year failure-free survival (FFS), the study aimed to recruit 222 patients but closed with 137, due to slow accrual.

RESULTS

One hundred thirty-one patients were included in this analysis. The complete response rates in the HD-CT and in the BEP arm did not differ: (intention to treat) 44.6% versus 33.3% (P = 0.18). There was no difference in FFS between the two treatment arms (P = 0.057, 66 events). At 2 years, the FFS rate was 44.8% [95% confidence interval (CI) 32.5-56.4] and 58.2%, respectively (95% CI 48.0-71.9); but this 16.3% (standard deviation 7.5%) difference was not statistically significant (P = 0.060). Overall survival did not differ between the two groups (log-rank P > 0.1, 47 deaths).

CONCLUSION

This study could not demonstrate that high-dose chemotherapy given as part of first-line therapy improves outcome in patients with poor-prognosis GCC.

A case series of embryonal rhabdomyosarcoma of the head and neck in adults

Embryonal rhabdomyosarcoma (RMS) is a rare malignant mesenchymal tumour that is believed to arise from cells committed to a skeletal muscle lineage. The head and neck region is among the most frequent locations for embryonal RMS in adults. We present a retrospective review of seven patients treated in our institution between 2000 and 2008. The age at diagnosis ranged from 19 to 41 years. One patient received primary surgery followed by adjuvant radiotherapy. Six inoperable patients were treated along a single chemotherapy protocol: the VIA-VIP regimen (a combination of vincristine, ifosfamide and doxorubicin (VIA) in alternation with etoposide, ifosfamide and cisplatin (VIP) administered in 3-weekly cycles), followed by local therapy, involving radiation therapy and/or surgery. An objective response to chemotherapy was observed in all six patients. Three out of seven patients remain disease-free with a median follow up of 4.5 years. Although the prognosis of head and neck embryonal RMS is worse in adults than in children, a multimodality treatment combining surgery, radiotherapy and intensive chemotherapy is feasible and effective in this population.

A phase I-II study of everolimus (RAD001) in combination with imatinib in patients with imatinib-resistant gastrointestinal stromal tumors

BACKGROUND

Imatinib is standard therapy for advanced gastrointestinal stromal tumors (GIST), but most patients develop resistance. This phase I-II study assessed the safety and efficacy of co-administering everolimus with imatinib in imatinib-resistant GIST.

PATIENTS AND METHODS

In phase I, patients received imatinib (600/800 mg/day) combined with weekly (20 mg) or daily (2.5/5.0 mg) everolimus to determine the optimal dose. In phase II, patients were divided into two strata (progression on imatinib only; progression after imatinib and sunitinib/other tyrosine kinase inhibitor) and received everolimus 2.5 mg plus imatinib 600 mg/day. Primary end point was 4-month progression-free survival (PFS).

RESULTS

Combination treatment was well tolerated. Common adverse events were diarrhea, nausea, fatigue, and anemia. In phase II strata 1 and 2, 4 of 23 (17%) and 13 of 35 (37%) assessable patients, respectively, were progression free at 4 months; median PFS was 1.9 and 3.5 months, and median overall survival was 14.9 and 10.7 months, respectively. In stratum 1, 36% had stable disease (SD) and 54% progressive disease (PD), while in stratum 2, 2% had partial response, 43% SD, and 32% PD.

CONCLUSION

Predetermined efficacy criteria were met in both strata. The combination of everolimus and imatinib after failure on imatinib and sunitinib merits further investigation in GIST.

A phase I dose finding study of the 3-day administration of BIBW 2992, an irreversible dual EGFR/HER-2 inhibitor, in combination with three-weekly docetaxel in patients with advanced solid tumors

3556

Background: BIBW 2992 (Tovok) is a potent, irreversible, new generation TKI, an inhibitor of EGFR and HER-2 (IC50 0.5 and 14 nM, respectively). A Phase I dose finding study of BIBW 2992 with docetaxel is reported. Methods: Patients (pts) had advanced solid malignancies and received docetaxel 75 mg/m2 i.v. on Day 1 and oral BIBW 2992 once daily on Days 2–4, in 3-week cycles. The BIBW 2992 dose was doubled in successive cohorts of 3–6 pts until ≥Grade 2 CTC, after which dose escalation occurred in increments of ≤50%. The MTD cohort expanded to 12 pts. PK profiles were taken on Days 1 and 2 of treatment cycles 1 and 2. Results: 40 evaluable pts (17 male) were treated at the following doses of BIBW 2992: 10 mg (6), 20mg (3), 40 mg (6), 60 mg (4), 90 mg (13), 120 mg (5) and 160 mg (3). Common adverse events (AEs) (% of patients) were fatigue (62.5%), diarrhea (57.5%), anorexia and stomatitis (52.5%), alopecia (50%), rash (42.5%), nausea and pyrexia (40%), vomiting (35%), general physical health deterioration (32.5%), and peripheral sensory neuropathy (30%). Two DLTs occurred: one pt had Grade 4 neutropenia (a DLT if complicated or lasting >5 or 7 days) and one had Grade 3 nausea, vomiting and diarrhea (BIBW 2992 120 mg). Both fully recovered upon treatment interruption/dose reduction (docetaxel 60 mg/m2/BIBW 2992 90 mg). The MTD was 90 mg BIBW 2992 with docetaxel 75 mg/m2. Four pts (breast cancer [2], thymoma [1], oesophageal carcinoma [1]) had a PR. One breast cancer pt had a confirmed CR. Two of these pts had prior taxane treatment. Ten pts had SD and received treatment for ≥6 courses with 4 receiving treatment for ≥9 courses. There was no deviation from dose-linearity of BIBW 2992 and docetaxel. Docetaxel (75 mg/m2) plasma concentration-time profiles, Cmax and AUC0-∞ before and after BIBW 2992 dosing were comparable. Conclusions: BIBW 2992 90mg administered for 3 days after docetaxel 75 mg/m2 is well tolerated and is the recommended dose for further trials. Objective responses or durable SD (≥6 months) were seen in 15 (39%) pts. No PK interaction was observed between BIBW 2992 and docetaxel.

[Table: see text]

Administration of 24-hour intravenous infusions of trabectedin every 3 weeks in ambulatory patients with mesenchymal tumors via disposable elastomeric pumps

e13530

Background: Patients (pts) with sarcoma whose disease progresses after standard chemotherapy have poor outcome. In this setting, DNA- transcription-interacting cytotoxic agent trabectedin (TRA) is efficacious and marketed in Europe. It is administered as 24-h i.v. infusion q3w with steroid co-medication. To overcome the inconvenience of hospitalization for drug delivery TRA is now given in Leuven via disposable elastomeric pumps, which facilitate ambulatory treatment and are compatible with the drug. Material and Methods: Heavily pre-treated pts with sarcoma were offered chemotherapy with TRA 1.5 mg/m2 as 24-h i.v. infusion via port catheter, either during hospitalization using electronic pumps or as outpatients using the Baxter LV10 disposable pump (drug dissolved in 267 ml NaCl 0.9%). Co-medication consisted of antiemetics and dexamethasone 2x4 mg days -1,1,2,3. Results: Between 09/07–12/08 28 pts were treated, and 21 (75%) elected outpatient therapy (9 F, 12 M, med. age 49 yrs, range 19–68). Common diagnoses included leiomyo- (5), lipo- (4), synovial (2) and myxofibrosarcomas. Pts had previous primary surgery (17), adjuvant RT (4) and surgery for relapse/metastasis (7). They had local relapse (2), distant metastasis (12) or both (7) when starting TRA, 19 had received previous chemotherapy with a med. number of 2 prior lines (range, 0–5). We administered 130 cycles of TRA in 21 pts, with a med. number of 3 cycles/patient (range, 1–24). Dose reductions were done in 60 cycles, mainly due to laborabory events. Best response (RECIST) was 3 confirmed PR, 1 PR pending confirmation, 6 SD, 11 PD. Grade 3/4 (CTC) AEs were limited to one case each of hemorrhage and lung embolism, other AEs were in line with published TRA experience. One port catheter contamination required replacement, one catheter tip thrombosis occurred and one extravasation due to needle dislocation was observed. Conclusions: Outpatient administration of TRA as 24-h infusion via port catheter using Baxter LV10 pumps is preferred by 3/4 pts, is feasible, safe, effective, cost-efficient and should be considered routine practice in this clinical setting.

[Table: see text]

Hypogonadism in male cancer patients treated with the tyrosine kinase inhibitors sunitinib (SUN) or sorafenib (SOR)

3565

Background: SUN and SOR are multi-targeted tyrosine kinase inhibitors (TKIs) inhibiting several kinases (VEGFR- 1,2; c-kit; PDGFR-α,β; flt-3; RET). SUN is approved for treatment of imatinib-resistant gastrointestinal stromal tumors (GIST) and metastatic renal cell carcinoma (RCC), SOR is used for RCC and hepatocellular carcinoma. We observed in some pts with fatigue under TKI treatment low testosterone (T) levels and started assessing the incidence and severity of gonadal dysfunction prospectively in male pts receiving these TKIs. Methods: Gonadal status (serum total testosterone (TT), free testosterone (FT), sex-hormone binding globulin (SHBG), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were evaluated in pts with RCC or GIST under SUN or SOR. SUN was given at a daily dose of 50 mg p.o. 4 weeks on, 2 weeks off, SOR at a daily oral dose of 800 mg. Results: We identified 27 pts (median age 63, range: 27–77), for which data on gonadal function were available, 23 RCC (85 %), 4 GIST (15%), with 22 (85.5%) receiving SUN and 5 (18.5%) SOR. Median treatment duration was 48 (2–202) weeks, 13 (48%) underwent dose reductions, in 4 (15%) pts due to grade 3 fatigue. All pts had at least once during TKI treatment T levels lower than normal (TT < 300 ng/dL and/or FT < 5 ng/dL), 17 (63%) had a low T with normal LH/FSH, 4 (15%) a low T with an elevated LH/FSH and 6 (22%) a low T and elevated FSH, but normal LH. The median TT level in the whole group was 194 ng/dL (21–477, normal range: 300–1,000 ng/dL), the median FT level in the whole group was 4.01 (0.45–9.07, normal range: 5–20 ng/dL). In the SUN cohort the median levels for TT and FT were slightly lower on day 28 in comparison to day 1 (184.5 vs 206 ng/dL for TT and 3.935 vs 4.225 ng/dl for FT). Pts with information available on testosterone at baseline (n = 8) tended to have slightly diminished baseline T levels (median: 222.5 [61–319] ng/dL), but 50% of these pts had been treated with other TKIs before. Two pts with grade 3 fatigue under SUN had very low T levels shortly after starting SUN (21 and 28 ng/dL, respectively). Conclusions: We observed a high incidence of hypogonadism in male RCC and GIST pts under treatment with SUN or SOR. Hypogonadism may likely contribute to the fatigue associated with these agents.

[Table: see text]

Docetaxel plus oblimersen sodium (Bcl-2 antisense oligonucleotide): an EORTC multicenter, randomized phase II study in patients with castration-resistant prostate cancer

BACKGROUND

This randomized, phase II study assessed the activity of oblimersen sodium, a Bcl-2 antisense oligonucleotide, administered before docetaxel (Taxotere) to patients with castration-resistant prostate cancer.

PATIENTS AND METHODS

Chemotherapy-naive patients with prostate-specific antigen (PSA) progression and testosterone < or = 0.5 ng/ml received docetaxel 75 mg/m2 on day 1 or oblimersen 7 mg/kg/day continuous i.v. infusion on days 1-7 with docetaxel 75 mg/m2 on day 5 every 3 weeks for < or = 12 cycles. Primary end points were confirmed PSA response (Bubley criteria) and major toxic events.

RESULTS

Confirmed PSA response was observed in 46% and 37% of 57 and 54 patients treated with docetaxel and docetaxel-oblimersen, respectively. Partial response (RECIST) was achieved in 18% and 24%, respectively. Oblimersen added to docetaxel was associated with an increase in the incidence of grade > or = 3 fatigue, mucositis, and thrombocytopenia. Major toxic events were reported in 22.8% and 40.7% of patients with docetaxel and docetaxel-oblimersen, respectively.

CONCLUSIONS

The primary end points of the study were not met: a rate of confirmed PSA response >30% and a major toxic event rate <45% were not observed with docetaxel-oblimersen.

The clinical implications of sunitinib-induced hypothyroidism: a prospective evaluation

Sunitinib is approved for the treatment of metastatic renal cell carcinoma (RCC) and imatinib-resistant or -intolerant gastrointestinal stromal tumours (GIST). Several studies have identified unexpected rates of thyroid dysfunction with sunitinib treatment. We performed a prospective observational study with the aim of more accurately defining the incidence and severity of hypothyroidism in RCC or GIST patients receiving sunitinib. Thyroid function was assessed at baseline and on days 1 and 28 of each treatment cycle. Thyroid antibodies were assessed at baseline and during follow-up if abnormal thyroid function tests were recorded. Sixteen patients (27%) developed sub- or clinical hypothyroidism and required hormone replacement and 20 patients (34%) showed at least one elevated thyroid-stimulating hormone not requiring therapeutic intervention. Twenty patients (34%) did not develop any biochemical thyroid abnormality. Thus, sunitinib can induce (sub-) clinical hypothyroidism, warranting close monitoring of thyroid function. We propose a new algorithm for managing this side effect in clinical practise.

Natural course and clinical features of myxoid and round cell liposarcoma (MRCL) - a retrospective single center analysis

10066

Background and methods: MRCL, the 2nd most common type liposarcoma, represents ∼10 % of adult soft tissue sarcomas. In most pts the karyotypic hallmark is t(12;16)(q13;p11), leading to fusion of CHOP and FUS genes and generation of a hybrid protein. MRCL has unique sensitivity to antineoplastic agent ET-743 (Yondelis, Trabectidin), which induces specific morphological change and long-lasting response. We made a retrospective analysis of MRCL cases in our center. Results: 33 pts had histological diagnosis of MRCL with a mean (mn) follow-up of 45 mo (range, 2–214). By karyotyping or FISH analysis CHOP-FUS fusion was present in 12 and CHOP-EWS in 2 pts. The mn age at diagnosis was 45 yrs (range, 18–71), male:female ratio 1:0.8. Frequent primary sites: lower limb (25), abdomen (5), retroperitoneum (2), neck (2). Stage grouping at diagnosis: IA (2), IB (6), IIA (5), III (14), IV (2), not known (NK) (4). 2 had distant spread, 9 metachronous metastasis with a mn interval of 24 mo (range, 5–84). Main sites involved: abdomen (5), lung (3), bone (3). Surgery was performed with curative intent in 26/28 pts (5 NK), R0 resection in 23. 17/28 pts are alive without disease (16 previously R0-resected). 6/28 are alive with disease, 5 died due to MRCL. Relapse after R0 resection occurred after a mn of 24 mo (range, 5–84). Radiotherapy was used in 15/28 (5NK) with neoadjuvant (1), adjuvant (13) or palliative (3) intent (total doses 50–66 Gy). Chemotherapy (CT) was given in palliative (11) or neoadjuvant (1) fashion, after a mn of 1.3 surgical interventions (range, 0–3). 1st-line CT: doxorubicin- based combinations (7), single-agent doxorubicin (3), ET-743 (1). Best response: PR (5), NC (4), PD (1), NE (1). Mn duration of response was 6.3 mo (range, 1–15). 2nd-line CT: ET-743 (3), other agents (4). Best response: CR (1), PR (1), NC (3), PD (1), NE (1), with mn response duration of 7 mo (range, 1–13). 2 had further CT (PR 1, SD 1). Conclusions: MRCL is a chemosensitive sarcoma with variable clinical course. Local treatment can be curative, but systemic spread is frequent. Pts may respond to conventional CT or new agents such as ET-743. To evaluate the relative value of systemic treatment we need randomized trials in this unique clinical setting.

No significant financial relationships to disclose.

A phase I study of nilotinib alone and in combination with imatinib (IM) in patients (pts) with imatinib-resistant gastrointestinal stromal tumors (GIST) - Study update

10023

Background: Nilotinib is a novel tyrosine kinase inhibitor (TKI) targeting KIT, PDGFR, and Bcr-Abl and inhibiting the proliferation of both IM-sensitive and -resistant cells in vitro. We report the results of a phase I study in GIST pts resistant to IM and other TKIs. Methods: Pts with progressive disease received nilotinib alone (400 mg p.o. bid) or escalating doses of nilotinib (200 mg qd, 400 mg qd, or 400 mg bid) in combination with IM (400 mg p.o. bid), or nilotinib 400 mg bid plus IM 400 mg qd. Pharmacokinetic (PK) analyses were performed. Tumor assessments (RECIST) were done every 8 weeks. Baseline samples of 18 GISTs were analyzed for KIT and PDGFR mutations. Results: 53 pts received nilotinib, alone (n=18) or in combination with IM (n=35), for a median of 134 days (range 8 to 430 days). Thirty-nine pts (74%) had failed second-line therapies including sunitinib, AMG-706, dasatinib or RAD001. Most frequent adverse events were grade 1 (17% of pts) or 2 (51% of pts) including: skin toxicity, fatigue, myalgia, headache, abdominal pain, nausea, vomiting, diarrhea, constipation, hyperbilirubinemia and edema. Six pts experienced dose limiting hyperbilirubinemia or skin rash. One pt on nilotinib alone achieved partial response (PR) for > 6 months and 36 pts (68%)-13 on nilotinib alone-, had SD ranging from 6 weeks to > 6 months. Median progression-free survival was 134 days overall and 178 days for pts on nilotinib alone. Genotyping revealed mutations in KIT exon 9 (n=4) or 11 (n=11), and KIT WT (n=3). The single PR occurred in KIT exon 11 mutant GIST following previous adjuvant imatinib and intolerance to imatinib 800 mg. KIT was WT in 2 out of 8 pts with SD > 6 months. Conclusions: Nilotinib, alone and in combination with IM has promising clinical activity in pts with GIST resistant to prior TKIs. Tolerability is acceptable for both nilotinib 400 mg bid, alone and in combination with IM 400 mg qd, which are the recommended doses for future studies.

No significant financial relationships to disclose.

Results of a phase I study of DTS-201, a peptidic prodrug of doxorubicin, in patients with solid tumors

2547

Background: DTS-201 is a promising prodrug of doxorubicin (dox) designed to preferentially deliver the parent compound to tumor cells and to limit cardiotoxicity. Based on animal studies showing that DTS-201 was markedly safer and more active than conventional dox, a phase I trial was conducted to determine safety, pharmacokinetics and the recommended dose (RD) for phase II studies. Methods: DTS-201 was given as 1-hour infusion every 3 weeks. Four dose levels were tested: 80, 160, 250 and 400 mg/m2 equivalent to 45 to 225 mg dox/m2. Toxicity was evaluated according to CTCAE v3.0 with specific attention to cardiotoxicity assessed by troponin I, echocardiography or cardio MUGA scan and 12-lead ECG. Results: Nineteen cancer patients (pts) with solid tumors (age range: 30–72 yrs) received DTS-201. Tolerance was good at 80 and 160 mg/m2. Three dose limiting toxicities (DLTs) were observed at cycle 1, one at 250 mg/m2 (grade 3 diarrhea) and two at 400 mg/m2 (one grade 3 vomiting and one grade 4 neutropenia = 5 days). Myelosuppression was the most common toxicity with 5 of the 6 pts treated at 400 mg/m2 experiencing transient asymptomatic grade 3–4 neutropenia on day 15 that spontaneously resolved. Other adverse reactions included mild to moderate asthenia, alopecia, anorexia and nausea. Neither cardiotoxicity or dox unrelated toxicities were observed. Disease stabilization for more than 4 cycles was observed in three pts with prostate cancer, pleural mesothelioma or bronchoalveolar carcinoma at 250 and 400 mg/m2. The pt with prostate cancer treated at 250 mg/m2 experienced a 60% decrease in serum PSA and a 23% reduction in lymph node size. The plasma AUCs and Cmax for DTS-201 and dox increased linearly with dose. At 400 mg/m2, the AUC of dox was within the range of values observed in pts receiving 60 mg/m2 of conventional dox. However the Cmax of dox, observed at 1 to 1.5 hours following DTS-201 administration, was 20 to 25 times lower. Conclusion: DTS-201 was well tolerated up to 400 mg/m2, corresponding to 3.750-fold the standard dose of dox. This dose, with no evidence of cardiac toxicity, was proposed to be the RD for future phase II studies. Six additional pts will be treated at that dose level to better characterize safety.

No significant financial relationships to disclose.

Ecteinascidin-743: evidence of activity in advanced, pretreated soft tissue and bone sarcoma patients

Purpose. To evaluate the activity and safety of ecteinascidin (ET-743) in pretreated patients with advanced or metastatic soft tissue and bone sarcoma. Patients or subjects. Eighty-nine patients received ET-743 as a 24-hour continuous infusion at a dose of 900-1500 mug/m(2) every 3 weeks. Results. We observed one complete remission, 5 partial remissions, one minimal response, and 16 patients with a disease stabilization of 6 months or more. The objective response rate was 6.7% and the clinical benefit rate at 3 and 6 months was 37.7% and 23.4%, respectively. Responses were noted in patients with lipo-, leiomyo-, osteo-, and myogenic sarcoma, with a median duration of 9.85 months. Toxicity mainly involved an asymptomatic elevation of transaminases and neutropenia. Estimated 1- and 2-year survival rates were 39.4% and 15.8%. Median overall survival was 8.25 months. Discussion. This retrospective analysis confirms that ET-743 induces objective responses and progression arrest in a clinically relevant proportion of patients.

Emerging role of tyrosine kinase inhibitors in the treatment of advanced renal cell cancer: a review

Advanced and metastatic renal cell cancer (RCC) is resistant to conventional chemotherapy. Only a very small number of patients survive long term after immunotherapy. However, any effect of interleukin-2 (IL-2) and/or interferon on median overall survival is small, and treatment-associated toxicities may be severe. The disease is therefore an area of high unmet medical need. Activation of the VEGF and EGF/RAS/RAF/MAP kinase pathways is frequent in solid tumours such as RCC. Such activation is implicated in tumour angiogenesis and proliferation. VEGF and EGF receptors and molecules (such as RAF kinase) involved in downstream signalling are therefore potential appropriate targets for drug therapy. Several antibodies and low molecular weight tyrosine kinase inhibitors (TKIs) have completed phase II clinical trials. Phase II studies of multitargeted agents, which include inhibition of VEGFR tyrosine kinase in their repertoire (sorafenib, sunitinib and AG 013736), show clear second-line activity in metastatic RCC. The same is true of the anti-VEGF antibody, bevacizumab. In a randomised phase III comparison against placebo in pretreated patients, sorafenib doubled median progression free survival (24 versus 12 weeks). Studies now in progress will determine whether benefits seen second-line will also be evident first-line, and whether the activity of novel agents can be increased by combining them with each other, with cytokines, or with chemotherapy.

Phase I and pharmacokinetic study of halofuginone, an oral quinazolinone derivative in patients with advanced solid tumours

PURPOSE

Halofuginone (tempostatin) is a synthetic derivative of a quinazolinone alkaloid showing anti-angiogenic, anti-metastatic and anti-proliferative effects in preclinical studies. The objectives of this phase I study were to assess the dose-limiting toxicities (DLTs), to determine the maximum tolerated dose (MTD) and to study the pharmacokinetics (PKs) of halofuginone when administered once or twice daily orally to patients with advanced solid tumours.

METHODS

Patients were treated with escalating doses of halofuginone at doses ranging from 0.5 to 3.5 mg/day. For pharmacokinetic analysis plasma sampling was performed during the first and second course and assayed using a validated high-performance liquid chromatographic assay with mass spectrometric detection.

RESULTS

Twenty-four patients received a total of 106 courses. The 'acute' MTD was reached at 3.5 mg/day, with nausea, vomiting, and fatigue as DLT. The recommended dose for chronic administration was defined as 0.5mg/day with the requirement of 5HT3 antagonists to control nausea and vomiting considered as DLT. Several patients experienced bleeding complications on treatment with halofuginone in which a causal relationship could not be excluded. The PKs of halofuginone were linear over the dose range studied with a large interpatient variability.

CONCLUSIONS

In this study the DLT of halofuginone was nausea, vomiting, and fatigue. The recommended dose for phase II studies of halofuginone is 0.5mg administered orally, once daily.

Sunitinib-related thyroid dysfunction: A single-center retrospective and prospective evaluation

3092

Background: Sunitinib is a multi-target tyrosine kinase inhibitor with anti-angiogenic and anti-proliferative activity mediated by signal blockade of VEGFR1/2, KIT, PDGFRα/β, and FLT-3. Phase II/III trials have demonstrated efficacy of the oral agent in Imatinib-resistant GIST and advanced renal cell cancer (RCC). We observed several cases of thyroid dysfunction in GIST during treatment with sunitinib suggesting that the drug may be associated with hypothyroidism. We therefore assessed the incidence and severity of thyroid dysfunction in cancer patients treated with sunitinib. Methods: Thyroid function (serum TSH, T3 and free thyroxin index) and thyroid antibodies (anti-TPO, -Tg and TSH-R-Ab) were evaluated retrospectively in a cohort of patients with GIST in a Phase III trial and in an expanded access program (1st part of the investigation) and in a prospective cohort of RCC and GIST patients treated in the framework of expanded access programs (2nd part). Sunitinib was given at a daily oral dose of 50 mg 4 weeks on, 2 weeks off. Thyroid parameters were assessed on days 1 and 28 of each treatment cycle in the prospective cohort. We report here the first TSH results, the full data set will be available at ASCO. Results: We identified a total of 46 patients who received sunitinib, and 33 of these patients were evaluable for thyroid function. 14 patients were analyzed retrospectively (all GIST), 19 patients prospectively (8 GIST, 11 RCC). 7 of these 19 patients (37%) showed an elevated TSH (>5 mIU/L) during treatment. In the retrospective analysis of 14 patients with a median treatment duration of 44 weeks, 8 patients (57%) had developed hypothyroidism. All patients with GIST in randomized Phase III trial remaining under active treatment with sunitinib for 58–80 weeks show an increased TSH (up to 83 mIU/L) during the course of treatment, requiring hormone substitution. In a cohort of 11 patients with RCC, after 6 weeks of treatment, 3 patients already have an increased TSH. Conclusions: Sunitinib is associated with a high incidence of thyroid dysfunction which requires further study. The mechanism by which Sunitinib induces thyroid dysfunction is yet unclear.

No significant financial relationships to disclose.

A phase I pharmacokinetic (PK) and molecular pharmacodynamic (PD) study of the combination of two anti-EGFR therapies, the monoclonal antibody (MAb) cetuximab (C) and the tyrosine kinase inhibitor (TKI) gefitinib (G), in patients (pts) with advanced colorectal (CRC), head and neck (HNC) and non-small cell lung cancer (NSCLC)

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Background: C and G are two anti-EGFR agents with different mechanisms of action. We had previously shown a synergistic effect combining the two agents in preclinical models (Matar et al, Clin Cancer Res 2004). This study aims to explore safety, PK and PD changes in tumor and skin at different doses of C/G to define the recommended dose (RD) for further development. Methods: pts were treated at the RD of weekly iv C (400 mg/m2 initial dose, 250 mg/m2 weekly) and oral daily G (250 mg/d) as single agents (5 pts each) and in successive cohorts of combined C/G (3–6 pts each): C (320/200) / G (100), C (400/250) / G (100), C (400/250) / G (250), C (320/200) / G (500) & C (400/250) / G (500) (ongoing). Dose escalation depended on dose limiting toxicity (DLT) rate during the first 28 d. Pre- & on-treatment steady-state (14 d) tumor & skin biopsies were obtained and have been evaluated by IHC for total (t) and phospho (p)-EGFR, p-MAPK, p-Akt, proliferation (Ki67), p27 expression and apoptosis by TUNEL. Gene profiling analysis is ongoing. Results: 35 pts have been treated so far: 20 CRC, 13 HNC & 2 NSCLC; median KI 90 % (70–100); median age 60 years (38–80); 24 males, 11 females. DLTs occurred in 3 pts: 1 pt with G alone with reversible ILD; 1 pt with G (250) / C (400/250) with reversible deafness & 1 pt with G (500) / C (320/200) with grade 3 anorexia and nausea. There were 1 CR (HNC) and 5 PRs (CRC) in the C/G cohorts, and 1 PR (CRC) in the C cohort. Overall, 5 out of 9 (56%) pts with CRC treated in the C/G cohorts presented a PR. PD studies show superior inhibition of p-EGFR, p-MAPK and p-Akt, reduction of proliferation and increased apoptosis (all p values <0.05) in the tumors of pts treated with C/G compared with the single agent cohorts. PK evaluation shows no PK interactions with the 2 drugs. Conclusions: This combination of an anti-EGFR MAb (C) and a TKI (G) is feasible at the RD of both agents. Our findings show encouraging clinical activity, especially in CRC, and superior PD signaling inhibition with the combination without any significant PK interaction. Combined anti-EGFR therapy deserves further evaluation.

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A phase I dose-finding clinical pharmacokinetic study of an oral formulation of irinotecan (CPT-11) administered for 5 days every 3 weeks in patients with advanced solid tumours

BACKGROUND

Oral administration of irinotecan (CPT-11) should allow sustained exposure to the drug without the inconvenience of intravenous delivery and with fewer side-effects.

PATIENTS AND METHODS

The present phase I trial of CPT-11, administered orally as a powder-filled capsule for 5 consecutive days every 3 weeks at doses ranging from 30 to 90 mg/m(2)/day, was conducted in 47 patients for whom a satisfactory standard treatment option was no longer available (24 males/23 females; median age 51 years, range 26-85). Tumour types included melanoma (11), colorectal (4), urinary tract (3), lung/pleura (4), thyroid (3), liver (3), gallbladder (2), cervix/uterus (3), breast (2), pancreas (2), carcinoma and other cancer types (10).

RESULTS

A total of 171 cycles were administered (median 3, range 1-11). Dose limiting toxicities (DLTs) occurred during the first cycle in five of 31 patients in the dose-escalation part of the study: one patient at the 50 mg/m(2)/day dose level (diarrhoea grade 4); one patient at the 80 mg/m(2)/day dose level (prolonged neutropenia grade 4 and diarrhoea grade 3); and three patients at the 90 mg/m(2)/day dose level (diarrhoea, vomiting and neutropenia). The 80 mg/m(2)/day dose level was expanded, as a feasibility study, to include 16 additional patients, five of whom had received extensive prior pelvic irradiation. A further three patients in this cohort experienced DLTs, two of whom had received extensive prior pelvic irradiation. One patient died on study day 15 during the first cycle of oral CPT-11 following grade 3 diarrhoea, febrile neutropenia and a necrotic enterocolitis. Overall the grade 3/4 toxicities in 47 patients were asthenia (19%), anorexia (17%), neutropenia (14.9 %), diarrhoea (13%), nausea (12.7%), vomiting (8.5%) and thrombocytopenia (8.5%). Partial responses were observed in two melanoma patients and disease stabilisation was noted in 17 (36.1%) patients. Pharmacokinetic parameters were recorded for 46 patients.

CONCLUSIONS

At the maximum tolerated dose, defined as 80 mg/m(2)/day for 5 days every 3 weeks, oral CPT-11 was shown to be well tolerated and safe with few of the haematological toxicities associated with the intravenous formulation.

Surgical interventions during STI 571 treatment of metastatic GIST: experience in six patients

Gastrointestinal stromal tumours (GIST), previously classified as smooth muscle tumours, are the most common mesenchymal tumours of the digestive tract. Since the discovery of KIT (CD 117) expression, these tumours can be diagnosed confidently by pathology. Until recently, surgery was the only treatment available because these tumours were not sensitive to chemotherapy nor radiation therapy. In the long run most of these tumours recurred in the abdominal cavity or in the liver. Recently a new drug STI 573 (Glivec) showed very promising results in metastatic disease with response rates of about 65%. In six patients treated at our center, surgery was indicated during STI therapy because of subobstruction, skin necrosis, abdominal distention, bleeding. Surgery proved to be safe and efficient, allowing continuation of STI therapy in much better circumstances.