Oral PD-L1 inhibitor GS-4224 selectively engages PD-L1 high cells and elicits pharmacodynamic responses in patients with advanced solid tumors

BACKGROUND

Checkpoint inhibitors targeting the programmed cell death 1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) pathway are effective therapies in a range of immunogenic cancer types. Blocking this pathway with an oral therapy could benefit patients through greater convenience, particularly in combination regimens, and allow flexible management of immune-mediated toxicities.

METHODS

PD-L1 binding activity was assessed in engineered dimerization and primary cell target occupancy assays. Preclinical antitumor activity was evaluated in ex vivo and in vivo human PD-L1-expressing tumor models. Human safety, tolerability, pharmacokinetics, and biomarker activity were evaluated in an open-label, multicenter, sequential dose-escalation study in patients with advanced solid tumors. Biomarkers evaluated included target occupancy, flow cytometric immunophenotyping, plasma cytokine measurements, and T-cell receptor sequencing.

RESULTS

GS-4224 binding caused dimerization of PD-L1, blocking its interaction with PD-1 and leading to reversal of T-cell inhibition and increased tumor killing in vitro and in vivo. The potency of GS-4224 was dependent on the density of cell surface PD-L1, with binding being most potent on PD-L1-high cells. In a phase 1 dose-escalation study in patients with advanced solid tumors, treatment was well tolerated at doses of 400-1,500 mg once daily. Administration of GS-4224 was associated with a dose-dependent increase in plasma GS-4224 exposure and reduction in free PD-L1 on peripheral blood T cells, an increase in Ki67 among the PD-1-positive T-cell subsets, and elevated plasma cytokines and chemokines.

CONCLUSIONS

GS-4224 is a novel, orally bioavailable small molecule inhibitor of PD-L1. GS-4224 showed evidence of expected on-target biomarker activity, including engagement of PD-L1 and induction of immune-related pharmacodynamic responses consistent with PD-L1 blockade.

TRIAL REGISTRATION NUMBER

NCT04049617.

Real-world outcomes of cisplatin, capecitabine, and gemcitabine with either epirubicin (PEXG) or docetaxel (PDXG) as first-line palliative treatment in metastatic or unresectable locally advanced pancreatic adenocarcinoma

BACKGROUND

First-line palliative chemotherapy regimens in advanced pancreatic adenocarcinoma include triplet chemotherapy with 5-fluorouracil, oxaliplatin, and irinotecan, and the doublet of nab-paclitaxel plus gemcitabine. Use of triplet chemotherapy in real-world populations is limited by tolerability and nab-paclitaxel is not universally available. Regimens using the combination of cisplatin, capecitabine, gemcitabine, and either epirubicin or docetaxel may be better tolerated, more widely available, and similarly effective, but no published real-world data exist.

METHODS

A retrospective cohort review of patients with metastatic or unresectable locally advanced pancreatic adenocarcinoma treated with first-line palliative cisplatin, capecitabine, gemcitabine, and either epirubicin or docetaxel chemotherapy at Auckland City Hospital between July 1, 2013 and July 30, 2020. The primary outcome was overall survival (OS). Secondary outcomes were rates of grade 3 or 4 hematological toxicity, rate of febrile neutropenia, number of cycles received, and reasons for discontinuation.

RESULTS

Eighty-eight patients were included. Median age was 66 years (range 39-79), 28.4% had unresectable, locally advanced disease and 71.6% metastatic disease. Median OS was 8.5 months. Patients stopped treatment due to disease progression (53.4%), completing 12 cycles (19.3%), or toxicity (10.2%). Grade 4 neutropenia was experienced by 21.6%; 10.2% had febrile neutropenia. There were four treatment-related deaths.

CONCLUSION

This retrospective study in a real-world population demonstrates that chemotherapy with cisplatin, capecitabine, and gemcitabine with epirubicin (PEXG) or docetaxel (PDXG) had similar effectiveness to more commonly used combination regimens. PDXG/PEXG are viable alternatives to nab-paclitaxel plus gemcitabine in countries that have restricted drug funding.

Response to BRAF-targeted Therapy Is Enhanced by Cotargeting VEGFRs or WNT/β-Catenin Signaling in BRAF-mutant Colorectal Cancer Models

The fact that 10% of colorectal cancer tumors harbor BRAF V600E mutations suggested targeting BRAF as a potential therapy. However, BRAF inhibitors have only limited single-agent efficacy in this context. The potential for combination therapy has been shown by the BEACON trial where targeting the EGF receptor with cetuximab greatly increased efficacy of BRAF inhibitors in BRAF-mutant colorectal cancer. Therefore, we explored whether efficacy of the mutant BRAF inhibitor vemurafenib could be enhanced by cotargeting of either oncogenic WNT/β-catenin signaling or VEGFR signaling. We find the WNT/β-catenin inhibitors pyrvinium, ICG-001 and PKF118-310 attenuate growth of colorectal cancer cell lines in vitro with BRAF-mutant lines being relatively more sensitive. Pyrvinium combined with vemurafenib additively or synergistically attenuated growth of colorectal cancer cell lines in vitro. The selective and potent VEGFR inhibitor axitinib was most effective against BRAF-mutant colorectal cancer cell lines in vitro, but the addition of vemurafenib did not significantly increase these effects. When tested in vivo in animal tumor models, both pyrvinium and axitinib were able to significantly increase the ability of vemurafenib to attenuate tumor growth in xenografts of BRAF-mutant colorectal cancer cells. The magnitude of these effects was comparable with that induced by a combination of vemurafenib and cetuximab. This was associated with additive effects on release from tumor cells and tumor microenvironment cell types of substances that would normally aid tumor progression. Taken together, these preclinical data indicate that the efficacy of BRAF inhibitor therapy in colorectal cancer could be increased by cotargeting either WNT/β-catenin or VEGFRs with small-molecule inhibitors.

Population pharmacokinetics for oral paclitaxel in patients with advanced/metastatic solid tumors

Oraxol consists of an oral dosage form of the chemotherapeutic agent paclitaxel administered with a novel P‐glycoprotein inhibitor encequidar methanesulfonate monohydrate (formerly named HM30181A), which allows oral treatment of cancers that would otherwise be treated with intravenous paclitaxel. Here we describe the population pharmacokinetics (popPK) analyses for oral paclitaxel in patients with advanced/metastatic solid tumors to characterize pharmacokinetic (PK) profiles and quantify sources of PK variability. The best fit popPK model for oral paclitaxel, based on data from seven clinical studies (197 patients with advanced/metastatic solid tumors), involves a linear two‐compartment structural model containing first‐order absorption with a short lag time and first‐order elimination as well as a log additive error. In this popPK model, lower population estimates of central volume for Asian patients versus Caucasian patients did not translate into clinical meaningful differences in oral paclitaxel exposure. Age, sex, body weight or surface area, mild hepatic impairment, and mild to moderate renal impairment had no clinically meaningful effects on the systemic exposure of oral paclitaxel. Simulations were performed on clinical therapeutic dose (oral paclitaxel 205 mg/m² once daily ×3 days per week) to predict exposure of oral paclitaxel and to support treatment benefits observed in a pivotal phase III trial.

Abstract CT557: Phase 1/2 study of quavonlimab (Qmab) + pembrolizumab (pembro) in patients (pts) with advanced melanoma that progressed on a PD-1/PD-L1 inhibitor

Background: Safe, effective treatment options for advanced melanoma that progressed on a PD-1/PD-L1 inhibitor is an unmet medical need. Results of the phase 1b KEYNOTE-029 trial showed promising antitumor activity in advanced melanoma with pembro combined with a CTLA-4 inhibitor. This ongoing, open-label, multiarm phase 1/2 study (NCT03179436) evaluating the CTLA-4 inhibitor Qmab + pembro showed antitumor activity as first-line treatment for advanced NSCLC and for previously treated extensive-stage SCLC. Data from the efficacy expansion phase in pts with advanced melanoma that progressed on a PD-1/PD-L1 inhibitor are presented.

Methods: Pts with unresectable stage III-IV melanoma and confirmed progressive disease (PD) per iRECIST within 12 wk of the last dose of a PD-1/PD-L1 inhibitor given alone or in combination for ≥2 doses (combinations with CTLA-4 inhibitors were not allowed) were randomly assigned (1:1) to receive Qmab 25 mg IV Q6W with or without pembro 400 mg IV Q6W; 100 pts in the Qmab + pembro arm and 40 pts in the Qmab monotherapy arm were planned for enrollment. Treatment in both arms was given for up to 18 cycles (~2 y) or until PD, toxicity, or pt withdrawal. Pts who had PD after ≥2 Qmab monotherapy cycles could crossover to Qmab + pembro. Tumor imaging was assessed Q9W to wk 54 and Q12W thereafter. Primary end points were safety and ORR by BICR per RECIST v1.1. Secondary and exploratory end points included DOR and PFS by BICR per RECIST v1.1 and OS.

Results: 151 pts were enrolled (n = 111, Qmab + pembro; n = 40, Qmab monotherapy); median time from first dose to database cutoff was 7.7 mo. In all pts, median age was 64 y; 66% of pts were male, 33% had BRAF-mutant tumors, and 50% had elevated LDH. Treatment-related adverse events (TRAEs) were reported in 87 pts (78%) in the Qmab + pembro arm and 24 pts (60%) in the Qmab monotherapy arm; grade 3/4 TRAEs were reported in 16 pts (14%) and 3 pts (8%), respectively. The most common TRAEs were pruritus (26%), fatigue (14%), diarrhea (14%), and rash (13%). No treatment-related deaths occurred in either arm; 5% of pts discontinued because of TRAEs. Confirmed ORR was 9% (95% CI, 4.4-15.9) with Qmab + pembro (1 CR, 9 PRs) and 3% (95% CI, 0.1-13.2) with Qmab monotherapy (1 PR). Median DOR was not reached (NR; range, 2.0+ to 13.8+ mo) with Qmab + pembro. DOR was 1.9+ with Qmab monotherapy. Median PFS was 2.1 mo (95% CI, 2.1-3.2) with Qmab + pembro and 2.1 mo (95% CI, 2.1-2.5) with Qmab monotherapy; 6-mo PFS rates were 21% and 13%, respectively. Median OS was NR (95% CI, 11.2 mo to NR) with Qmab + pembro and 7.8 mo (95% CI, 6.3 to NR) with Qmab monotherapy; 6-mo OS rates were 74% and 73%, respectively.

Conclusions: Qmab + pembro was generally well tolerated and provided modest antitumor activity in pts with advanced melanoma that progressed on a PD-1/PD-L1 inhibitor. This combination and a coformulation of Qmab + pembro will be further investigated in the KEYMAKER-U02 study.

Citation Format: Sanjeev Deva, Jacek Mackiewicz, Stephane Dalle, Helen Gogas, Iwona Lugowska, Alfonso Berrocal, Alexander M. Menzies, Michele Maio, Adnan Nagrial, Karmele Mujika Eizmendi, Jean-Jacques Grob, Christian Caglevic, Megan Lyle, Juan Martin-Liberal, Rachel Altura, Yixin Ren, Anuradha Khilnani, Jobin Cyrus, Shabana Siddiqi, Michal Lotem. Phase 1/2 study of quavonlimab (Qmab) + pembrolizumab (pembro) in patients (pts) with advanced melanoma that progressed on a PD-1/PD-L1 inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT557.

Intralesional SD-101 in Combination with Pembrolizumab in Anti-PD-1 Treatment-Naïve Head and Neck Squamous Cell Carcinoma: Results from a Multicenter, Phase II Trial

PURPOSE

To determine whether SD-101, a Toll-like receptor 9 agonist, potentiates the antitumor activity of anti-PD-1 antibodies in patients with anti-PD-1/PD-L1 naïve, recurrent/metastatic head and neck squamous cell carcinoma (HNSCC).

PATIENTS AND METHODS

Patients with PD-1 Ab-naïve HNSCC received either 2 mg SD-101 injected in one to four lesions or 8 mg SD-101 injected into a single lesion weekly × 4 doses then every 3 weeks × 7 doses. Pembrolizumab was administered at 200 mg every 3 weeks.

RESULTS

A total of 28 patients received 2 mg and 23 received 8 mg per injection, respectively. A total of 76% of patients had received prior systemic therapy. Combined positive score was ≥1 to < 20 in 35 patients (70%) and ≥ 20 in 15 patients (30%) of 50 patients with available data. There were 12 patients with grade ≥3 treatment-related adverse events (24%), and no treatment-related deaths. The objective response rate was 24% including 2 complete and 10 partial responses. The median duration of response was 7.0 [95% confidence interval (CI): 2.1-11.1] months. The response rate was higher in human papillomavirus-positive (HPV+) patients (44%, N = 16). Responses were not associated with PD-L1 expression levels or IFNγ-related gene expression at baseline. Responses were observed both in injected (32%) and in noninjected lesions (29%). Progression-free and overall survival at 9 months were 19.0% (95% CI: 9.1-31.7) and 64.7% (95% CI: 45.3-78.7), respectively.

CONCLUSIONS

SD-101 combined with pembrolizumab induced objective responses, especially in HPV+ tumors, which were frequently associated with increased intratumoral inflammation and effector immune cell activity.

Phase IA/IB study of single-agent tislelizumab, an investigational anti-PD-1 antibody, in solid tumors

Background

The programmed cell death-1/programmed cell death ligand-1 (PD-1/PD-L1) axis plays a central role in suppressing antitumor immunity; axis dysregulation can be used by cancer cells to evade the immune system. Tislelizumab, an investigational monoclonal antibody with high affinity and binding specificity for PD-1, was engineered to minimize binding to FcγR on macrophages to limit antibody-dependent phagocytosis, a potential mechanism of resistance to anti-PD-1 therapy. The aim of this phase IA/IB study was to investigate the safety/tolerability, antitumor effects and optimal dose and schedule of tislelizumab in patients with advanced solid tumors.

Methods

Patients (aged ≥18 years) enrolled in phase IA received intravenous tislelizumab 0.5, 2, 5 or 10 mg/kg every 2 weeks; 2 or 5 mg/kg administered every 2 weeks or every 3 weeks; or 200 mg every 3 weeks; patients in phase IB received 5 mg/kg every 3 weeks. Primary objectives were to assess tislelizumab’s safety/tolerability profile by adverse event (AE) monitoring and antitumor activity using RECIST V.1.1. PD-L1 expression was assessed retrospectively with the VENTANA PD-L1 (SP263) Assay.

Results

Between May 2015 and October 2017, 451 patients (n=116, IA; n=335, IB) were enrolled. Fatigue (28%), nausea (25%) and decreased appetite (20%) were the most commonly reported AEs. Most AEs were grade 1–2 severity; anemia (4.9%) was the most common grade 3–4 AE. Treatment-related AEs led to discontinuation in 5.3% of patients. Grade 5 AEs were reported in 14 patients; 2 were considered related to tislelizumab. Pneumonitis (2%) and colitis (1%) were the most common serious tislelizumab-related AEs. As of May 2019, 18% of patients achieved a confirmed objective response in phase IA and 12% in phase IB; median follow-up duration was 13.6 and 7.6 months, respectively. Pharmacokinetics, safety and antitumor activity obtained from both phase IA and IB determined the tislelizumab recommended dose; ultimately, tislelizumab 200 mg intravenous every 3 weeks was the dose and schedule recommended to be taken into subsequent clinical trials.

Conclusions

Tislelizumab monotherapy demonstrated an acceptable safety/tolerability profile. Durable responses were observed in heavily pretreated patients with advanced solid tumors, supporting the evaluation of tislelizumab 200 mg every 3 weeks, as monotherapy and in combination therapy, for the treatment of solid tumors and hematological malignancies.

Trial registration number

NCT02407990.

Oral paclitaxel with encequidar compared to intravenous paclitaxel in patients with advanced cancer: A randomised crossover pharmacokinetic study

AIMS

Paclitaxel is a widely used anti-neoplastic agent but has low oral bioavailability due to gut extrusion by P-glycoprotein (P-gp). Oral paclitaxel could be more convenient, less resource intensive, and more tolerable than intravenous administration. Encequidar (HM30181A) is a novel, minimally absorbed gut-specific P-gp inhibitor. We tested whether administration of oral paclitaxel with encequidar (oPac+E) achieved comparable AUC to intravenous paclitaxel (IVP) 80 mg/m² .

METHODS

We conducted a multi-centre randomised crossover study with two treatment periods. Patients (pts) with advanced cancer received either oral paclitaxel 615 mg/m² divided over 3 days and encequidar 15 mg orally 1 hour prior, followed by IVP 80 mg/m² , or the reverse sequence. PK blood samples were taken up to Day 9 for oPac+E and Day 5 for IVP.

RESULTS

Forty-two patients were enrolled; 35 completed both treatment periods. AUC_0-∞ was 5033.5 ± 1401.1 ng.h/mL for oPac+E and 5595.9 ± 1264.1 ng.h/mL with IVP. The geometric mean ratio (GMR) for AUC was 89.50% (90% CI 83.89-95.50). Mean absolute bioavailability of oPac+E was 12% (CV% = 23%). PK parameters did not change meaningfully after 4 weeks administration of oPac+E in an extension study. G3 treatment-emergent adverse events occurred in seven (18%) pts with oPac+E and two (5%) with IVP. Seventy-five per cent of patients preferred oPac+E over IVP.

CONCLUSIONS

GMR for AUC was within the predefined acceptable range of 80-125% for demonstrating equivalence. oPac+E is tolerable and there is no evidence of P-gp induction with repeat administration. With further study, oPac+E could be an alternative to IVP.

Immune- and tumor-intrinsic gene expression profiles of response or resistance to tislelizumab as monotherapy or in combination with chemotherapy in non-small cell lung cancer (NSCLC)

e15258

Background: Tislelizumab, an anti-PD-1 monoclonal antibody, showed clinical benefit for patients (pts) with NSCLC alone (NCT02407990, CTR20160872) and in combination with chemotherapy (NCT03432598). Gene expression profiles (GEP) associated with response and resistance to tislelizumab in these studies were assessed. Methods: The GEP of baseline tumor samples from 59 nonsquamous (NSQ) and 42 squamous (SQ) NSCLC pts treated with tislelizumab monotherapy (mono) as ≥1L treatment, and 16 NSQ and 21 SQ pts treated with tislelizumab plus chemotherapy (combo) as 1L treatment were assessed using the 1392-gene HTG GEP EdgeSeq panel. NSQ and SQ cohorts were analyzed separately due to distinct GEP features shown by PCA and t-SNE clustering. Results: Tislelizumab mono and combo showed antitumor activity in NSCLC (Table). In 80 biomarker-evaluable samples, inflamed tumor signatures (inflammatory GEP; antigen presentation GEP) were associated with longer overall survival (log-rank test, NSQ mono: P=0.04, 0.003; NSQ combo: P=0.05, 0.02; SQ combo: P=0.06, 0.06). Monotherapy non-responders (NRs) were clustered into 2 subgroups (NR1, NR2) with distinct GEPs. Compared with responders, NR1 had proliferation signatures (elevated cell cycle [CC] and DNA repair) in both NSQ ( P=0.2, 0.02) and SQ ( P=0.03, 0.4) cohorts, trending toward low inflamed tumor signatures. In NR pts receiving combo, CC and DNA repair signatures were not enriched, and high CC and DNA repair scores were observed in some SQ combo responders versus NRs ( P=0.2, 0.02). NR2 had higher M2 macrophage and Treg cell signatures versus responders in both NSQ and SQ mono, despite high inflamed tumor and low proliferation signatures. NR2 also had increased expression of genes related to immune regulation and angiogenesis, including PIK3CD, CCR2, CD244, IRAK3, and MAP4K1 ( P<0.05) in NSQ, and PIK3CD, CCR2, CD40, CD163, MMP12, VEGFC, and TEK ( P<0.05) in SQ. Conclusions: Clinical benefit in pts with NSCLC receiving tislelizumab (mono or combo) was associated with high inflamed tumor signatures, while elevated immune suppressive cell signatures may indicate resistance. High proliferation signatures were associated with resistance to monotherapy, but not to combination therapy. Both immune- and tumor-intrinsic factors may be considered for validation in future clinical trials. [Table: see text]

First-line durvalumab + monalizumab, mFOLFOX6, and bevacizumab or cetuximab for metastatic microsatellite-stable colorectal cancer (MSS-CRC)

128

Background: Targeting multiple immune checkpoint pathways and combining checkpoint inhibition with chemotherapy may enhance response in MSS-CRC. In a Phase 1/2, multicenter, open-label study, the anti-PD-L1 antibody durvalumab (D) was added to monalizumab (M; an anti-NKG2A antibody). In dose-exploration cohorts, D+M was added to chemotherapy and a biologic agent (bevacizumab [DMCB] or cetuximab [DMCC]) for first-line treatment of advanced/metastatic MSS-CRC. Initial data showed DMCB was well tolerated and clinically active. Here we report updated efficacy and safety of DMCB and initial safety of DMCC. Methods: Eligible patients (pts) had MSS-CRC ( RAS/BRAF wt with a left-sided colon primary tumor in the DMCC cohort) and ECOG PS 0–1. They received D 1500 mg Q4W, M 750 mg Q2W, mFOLFOX6 Q2W and bevacizumab 5 mg/kg Q2W or cetuximab 250/400 mg/m2 QW (up to 500 mg/m2 Q2W) for up to 3 yr. The primary endpoint was safety and tolerability; secondary endpoints included antitumor activity. Results: As of Aug 26, 2019, 18 pts received DMCB and 17 pts received DMCC. Treatment-emergent adverse events (AEs) occurred in 100.0% of the DMCB cohort (most commonly fatigue, nausea and peripheral neuropathy) and 94.1% of the DMCC cohort (most commonly peripheral neuropathy, rash and dermatitis acneiform). The AEs were grade 3/4 in 77.8% of pts receiving DMCB and 70.6% of pts receiving DMCC, and were serious in 38.9% and 47.1%, respectively. Response was evaluable in 17 pts receiving DMCB; objective response rate was 41.2% (all PRs; Table). Responses occurred early and the median duration of response has not yet been reached. Conclusions: In advanced/metastatic MSS-CRC, first-line DMCB and DMCC had a manageable safety profile and DMCB showed promising preliminary activity. Clinical trial information: NCT02671435.

[Table: see text]

Corrigendum to "Joint Consensus Statement of the Indian National Association for Study of the Liver and Indian Radiological and Imaging Association for the Diagnosis and Imaging of Hepatocellular Carcinoma Incorporating Liver Imaging Reporting and Data System" [J Clin Expt Hepatol 9 (2019) 625-651]

[This corrects the article DOI: 10.1016/j.jceh.2019.07.005.].

Abstract CT084: Long-term exposure (LTE) to Tislelizumab, an investigational anti-PD-1 antibody, in a first-in-human Phase I study

Background Tislelizumab (BGB-A317), an investigational monoclonal antibody with high affinity and specificity for PD-1, was engineered to minimize binding to FcγR on macrophages in order to abrogate antibody-dependent phagocytosis, a potential mechanism of resistance to anti-PD-1 therapy. Previous reports from early phase studies suggest tislelizumab was generally well tolerated and had antitumor activity in patients (pts) with advanced solid tumors. Clinical effects of tislelizumab LTE (&gt;12 mo) in pts enrolled in the first-in-human study (NCT02407990) are presented here.

Methods Patients with advanced solid tumors received IV tislelizumab 0.5, 2, 5, or 10 mg/kg Q2W, 2 or 5 mg/kg administered Q2W or Q3W, or 200 mg IV Q3W. Antitumor activity was assessed by RECIST v1.1 criteria; PD-L1 expression was retrospectively assessed with the VENTANA PD-L1 (SP263) assay.

Results As of 31 Aug 2018, 63 of the 451 pts received tislelizumab for &gt;12 mo. In these 63 pts, median age was 64 yr and 70% had received ≥1 prior systemic therapy. Tislelizumab LTE was most common in NSCLC (n=9), HCC (n=7), and bladder and ovarian (n=5 each) cancers. Four of the 5 pts who achieved CR during this study had LTE to tislelizumab (Table); all 4 pts were PD-L1+ (≥1% expression on tumor cells). Across the LTE cohort, ORR was 66.7%; PR and SD were observed in both PD-L1+ and PD-L1- tumors. The median time to CR/PR (3.7 mo) and duration of CR/PR (21.1 mo) were longer in pts with LTE than pts who responded but did not remain on treatment for &gt;12 mo (2.1 and 6.3 mo, respectively). Rash was the only treatment-related AE (TRAE) reported in ≥15% of pts. Most TRAEs were of mild or moderate severity; arthritis, diarrhea, fatigue, granuloma, hyperglycemia, and lichenoid keratosis (n=1 each) were the only grade ≥3 TRAEs reported with tislelizumab LTE.

Conclusion Tislelizumab remained well tolerated for &gt;12 mo and elicited durable responses in pts with a variety of tumor types regardless of PD-L1 status.

PD-L1+ (n=35)PD-L1- (n=22)Missing (n=6)Total (N=63)CR4004 (6.3%)PR2113438 (60.3%)SD99220 (31.7%)PD1001 (1.6%)Abbreviations: CR, complete response; PD, progressive disease; PR, partial response; SD stable disease.

Citation Format: Jayesh Desai, Benjamin Markman, Michael Friedlander, Hui Gan, Lisa Horvath, Amanda Townsend, Michael Millward, Michael Jameson, Chia-Jui Yen, Ming-Mo Hou, Jeannie Hou, John Wu, Liang Liang, Sanjeev Deva. Long-term exposure (LTE) to Tislelizumab, an investigational anti-PD-1 antibody, in a first-in-human Phase I study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT084.

Phase 1b/2, open label, multicenter study of intratumoral SD-101 in combination with pembrolizumab in anti-PD-1 treatment naïve patients with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC)

6039

Background: SD-101, a synthetic CpG-ODN agonist of TLR9, stimulates dendritic cells to release IFN-alpha and mature into antigen presenting cells - activating T cell anti-tumor responses. Pembrolizumab has demonstrated activity in HNSCC. Study DV3-MEL-01 (NCT02521870) assesses safety and efficacy of SD-101 in combination with pembrolizumab in patients with recurrent/metastatic HNSCC. We have previously reported a 27.3% ORR in 22 patients receiving 8 mg SD-101/injection in the modified ITT after at least 2 CT scans due to late responses (Abstract 3560, ESMO 2018). Higher efficacy at a lower SD-101 dose, 2 mg/injection, has been reported in advanced melanoma patients (LBA 45, ESMO 2018). Consequently, this dose is now being assessed in HNSCC. We report preliminary data with the 2 mg/injection dose in 23 patients in mITT at the first CT scan. Methods: Anti-PD-1/PD-L1 naïve patients received 2 mg SD-101 intratumorally in 1 - 4 lesions (weekly x 4 doses then Q3W x 7 doses). Pembrolizumab is was administered IV at 200 mg Q3W. Responses were assessed per RECIST v1.1. Results: 28 patients enrolled: median age 63 y/o, male 68%; ECOG PS 0-1 (18%/82%); mean prior lines of systemic therapy 1 (0-3); mean treatment duration 70 days (1-253). Primary tumors: 19 (68%) oropharyngeal; 3 (10%) laryngeal; 2 (7%) hypopharyngeal; 4 (14%) unknown. Mean number of target lesions: 1.82 (1 to 5). HPV status: 7 (25%) +, 9 (32%) -, 12 (43%) unknown. 18 (64 %) discontinued treatment: 12 (42%) due to PD, 4 (16%) deaths, 1 (3%) consent withdrawn, 1 (3%) went to hospice. Mean follow up 2.70 months. Safety: 16 non-treatment-related SAEs in 9 patients. 2 treatment-related Grade ≥3 AEs: sepsis (4%) and lymphopenia (4% ). No treatment-related deaths. Efficacy: 23 patients in the mITT population with first CT scan at day 64: ORR: CR: 2, PR: 3 (22%); SD: 6 (26%), PD: 7 (30%), non-evaluable: 5 (22%). Disease control rate (48%). 5 patients on study have not had a CT scan. Conclusions: SD-101 with Pembrolizumab shows early promising data and is well tolerated. Additional follow-up scans from both dose cohorts are being evaluated and will be presented. Clinical trial information: NCT02521870.

Joint Consensus Statement of the Indian National Association for Study of the Liver and Indian Radiological and Imaging Association for the Diagnosis and Imaging of Hepatocellular Carcinoma Incorporating Liver Imaging Reporting and Data System

Hepatocellular carcinoma (HCC) is the 6th most common cancer and the second most common cause of cancer-related mortality worldwide. There are currently no universally accepted practice guidelines for the diagnosis of HCC on imaging owing to the regional differences in epidemiology, target population, diagnostic imaging modalities, and staging and transplant eligibility. Currently available regional and national guidelines include those from the American Association for the Study of Liver Disease (AASLD), the European Association for the Study of the Liver (EASL), the Asian Pacific Association for the Study of the Liver, the Japan Society of Hepatology, the Korean Liver Cancer Study Group, Hong Kong, and the National Comprehensive Cancer Network in the United States. India with its large population and a diverse health infrastructure faces challenges unique to its population in diagnosing HCC. Recently, American Association have introduced a Liver Imaging Reporting and Data System (LIRADS, version 2017, 2018) as an attempt to standardize the acquisition, interpretation, and reporting of liver lesions on imaging and hence improve the coherence between radiologists and clinicians and provide guidance for the management of HCC. The aim of the present consensus was to find a common ground in reporting and interpreting liver lesions pertaining to HCC on imaging keeping LIRADSv2018 in mind.

Mortality within 30 days of systemic anticancer therapy at a tertiary cancer centre: assessing the safety and quality of clinical care

AIMS

Thirty-day mortality has been proposed to be a useful indicator of avoidable harm to patients from systemic anticancer therapies (SACT). As a quality assurance tool, we assessed the 30-day mortality rate at Auckland City Hospital and compared this with international standards.

METHODS

Clinical characteristics and treatment details of medical oncology patients who died within 30 days of SACT from October 2014-September 2015 were collected and compared with data from a similar series performed from October 2008-September 2009. SACT was limited to chemotherapy or biologic agents.

RESULTS

From October 2014-September 2015, 1,965 patients received 2,145 treatment regimens. Forty-seven patients (2.2%) died within 30 days of SACT. Treatment was given with palliative intent in 42 patients (in 89%) and curative intent in five (11%). Mortality rates did not change with time (2.8% in 2009 vs 2.2% in 2015). Of the patient who died within 30 days, ECOG performance status at the time of chemotherapy was one in 16 patients (34.0%), two in nine patients (19.1%) and 3/4 in nine of the 47 patients (19.1%). All patients treated with curative intent had a PS of 0 or 1. Most patients who died within 30 days were on first- or second-line therapy (45 and 38% respectively). Two-thirds of patients with a PS of 3/4 were receiving first-line therapy. Approximately half the patients died during their first cycle of therapy (48.9%).

CONCLUSIONS

Our local 30-day mortality data compares favourably to international benchmarks of 5% and has not increased over time. Performance of similar studies locally and nationally should be undertaken to continue to assess and improve the quality of our patient care.

Abstract P4-14-26: Phase I expansion of S-222611, a reversible inhibitor of EGFR and HER2, in advanced solid tumors, including HER2-positive breast cancer patients with brain metastases

BACKGROUND

S-222611 is an oral, reversible ErbB tyrosine kinase inhibitor of EGFR and HER2 with potent pre-clinical activity. MTD was not reached during the dose-escalation phase, (maximum dose 1600 mg QD). PK and efficacy data supported a daily dose of 800 mg. An expansion cohort of patients has been treated to further explore safety and efficacy.

METHODS

Subjects with advanced solid tumors expressing EGFR and/or overexpressing HER2 were enrolled. S-222611 800 mg daily was administered until disease progression or unacceptable toxicity.

RESULTS

76 patients were included in this phase 1 expansion cohort with a variety of tumor types. Dose reduction was required because of adverse events in 15 patients; the most frequent of which being diarrhea and elevated bilirubin. Two patients discontinued treatment due to drug- related adverse events. Of the 25 patients with HER2-positive metastatic breast cancer (MBC), 4 partial responses were observed, and prolonged stable disease (≥ 6 months) was observed in 3 additional patients. These 25 patients had received prior HER2-directed therapy as shown in Table 1.

Table 1. Prior therapies received by patients with HER2-positive MBCPrior therapyn (%)Trastuzumab22 (88)T-DM13 (12)Lapatinib16 (64)Chemotherapy23 (92)

Six of these patients had brain metastases, in whom 1 intracranial response and 2 prolonged stable disease (≥ 6 months) were observed (Table 2).

Table 2. HER2-positive MBC patients with brain metastases - best overall response to S-222611Pts #HER2 IHCBrain metastasesBest overall response (RECIST 1.1)Patient 13+Target lesionPRPatient 23+Target lesionSD (≥12 M)Patient 33+Target lesionSD (6.0 M)Patient 43+Non-target lesionSD (4.7 M)Patient 53+Non-target lesionSD (3.3 M)Patient 63+Non-target lesionNE

The patient showing intracranial response was previously treated with lapatinib and capecitabine after diagnosis of BM.

CONCLUSIONS

S-222611 was well tolerated at a dose of 800 mg once daily. Anti-tumour activity, including shrinkage of brain metastases, was evident in a heavily pre-treated population of patients with HER2-positive breast cancer.

Citation Format: Baird RD, Arkenau H-T, Deva S, Cresti N, Garcia-Corbacho J, Hogarth L, Frenkel E, Kawaguchi K, Arimura A, Donaldson K, Posner J, Sarker D, Jodrell D, Plummer R, Spicer J, Italiano A. Phase I expansion of S-222611, a reversible inhibitor of EGFR and HER2, in advanced solid tumors, including HER2-positive breast cancer patients with brain metastases. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-14-26.

Dose-intense capecitabine, oxaliplatin and bevacizumab as first line treatment for metastatic, unresectable colorectal cancer: a multi-centre phase II study

BACKGROUND

Dose intense chemotherapy may improve efficacy with acceptable toxicity. A phase II study was conducted to determine the feasibility of a dose-intense two weekly schedule of capecitabine, oxaliplatin, and bevacizumab in metastatic colorectal cancer (mCRC).

METHODS

49 patients with previously untreated mCRC were recruited. Nineteen received capecitabine (1750 mg/m(2) oral BD days 1-7)oxaliplatin (85 mg/m(2)i.v. day 1) and bevacizumab (5 mg/kg i.v. day 1) using a 14-day cycle (C1750). Following toxicity concerns capecitabine was reduced to 1500 mg/m2oral BD (C1500) and 30 further patients recruited.

RESULTS

Over 80% of patients received at least 75% of planned chemotherapy doses over the first two cycles. At C1750 Grade 3 or higher toxicity occurred in 74% (95% CI 49% to 91%) and on C1500 in 70% (95% CI 51% to 85%). The median progression-free survival was 6.9 months (95% CI 4.7 to 8.7) for C1750 dose and 8.9 months (95% CI 4.1 to 12.4) for C1500. 3 treatment-related deaths occurred.

CONCLUSIONS

Dose intense capecitabine and oxaliplatin with bevacizumab does not show additional efficacy and has potentially significant toxicity. Its use outside of clinical trials is not recommended.

TRIAL REGISTRATION

ISRCTN41540878.

Everolimus and zoledronic acid in patients with renal cell carcinoma with bone metastases: a randomized first-line phase II trial

BACKGROUND

Bone metastases from renal cell carcinoma (RCC) are a major cause of morbidity. Post hoc analysis has suggested that bone turnover markers can identify patients at risk of skeletal-related events (SREs) among those receiving zoledronic acid. This study sought to evaluate the effect on bone metastases of everolimus alone compared with everolimus plus zoledronic acid.

PATIENTS AND METHODS

Thirty treatment-naive patients with RCC and ≥ 1 bone metastases were randomized 1:1 to everolimus (10 mg daily) versus everolimus plus zoledronic acid (4 mg intravenously 4-weekly). Bone-specific assessments were performed at baseline and at weeks 1, 4, 8, and 12. Treatment was continued on allocated arm until progression per RECIST 1.1 (Response Evaluation Criteria in Solid Tumors, version 1.1). The primary outcome measure was urine N-telopeptide (uNTX) level, with secondary measures of plasma C-telopeptide (CTX), quality of life (Functional Assessment of Cancer Therapy-Bone Pain [FACT-BP], Brief Pain Inventory [BPI]), progression-free survival (PFS), SREs, and safety.

RESULTS

After 12 weeks, reduction in mean uNTX and CTX on everolimus plus zoledronic acid relative to everolimus was 68.4% (95% CI, 60.1%-74.9%; P < .0001) and 76.2% (95% CI, 67.3%-82.7%; P < .0001), respectively. There was no evidence of a difference for FACT-BP (P = .5), but evidence was favorable for BPI Severity (P = .05) and BPI Interference (P = .06). Median PFS was 7.5 months (95% CI, 3.4-11.2) on everolimus plus zoledronic acid and 5.4 months (95% CI, 3.2-6.3) on everolimus (P = .009). Median time to first SRE was 9.6 months (95% CI, 4.3-15.5) on everolimus plus zoledronic acid and 5.2 months (95% CI, 1.6-8.2) on everolimus (P = .03).

CONCLUSION

In this RCC population, the addition of zoledronic acid to everolimus significantly reduced bone resorption markers and may prolong tumor control.

RAD001 and zoledronic acid in patients with renal cell carcinoma with bone metastases (RAZOR): A randomized phase II trial

402

Background: Bone metastases (BM) from renal cell carcinoma (RCC) are common, cause morbidity, and have been identified as an adverse prognostic feature. Previous trials have not assessed the effects of modern therapies on BM from RCC. Randomized data has demonstrated that zoledronic acid (Z) reduces skeletal-related-events (SREs) in RCC patients (pts). Bone turnover markers can identify pts at risk of SREs among those receiving Z. We sought to evaluate the effect on BM of RAD001 (R) (everolimus) alone compared to R+Z in the first-line setting. Methods: 30 treatment naïve pts with RCC and ≥ 1 BM were randomized 1:1 to R 10mg daily vs. R+Z 4mg IV 4-weekly (dose adjusted for creatinine clearance [CrCl]). Key eligibility criteria were ECOG PS ≤ 2, no bisphosphonates, or radiotherapy within 4 wks and CrCl >35ml/min. Bone-specific assessments were performed at baseline, wks-1, 4, 8, and 12. Treatment was continued on allocated arm until progression (RECIST 1.1). The primary objective was to assess the difference in bone turnover markers over the first 12 wks. The primary endpoint was urine N-telopeptide (uNTX) level with secondary endpoints being plasma C-telopeptide (CTX), quality of life (FACT-BP, BPI), progression free survival (PFS), SREs, and safety. Results: Heng prognostic group poor, intermediate, and good risk was 20.0%, 46.7%, 33.3% in R+Z and 40.0%, 46.7%, 13.3% in R. Over first 12 wks, the reduction in mean: uNTX on R+Z relative to R was 68.4% (95% CI (60.1%, 74.9%); p<0.0001); CTX on R+Z relative to R was 77% (95% CI (68%, 83%); p<0.0001). For FACT-BP there was no evidence of a difference (p = 0.5) but addition of Z was favourable for BPI Severity -1.1 (-2.2, 0.23; p = 0.05) and BPI Interference -1.3 (-2.5, 0.03; p = 0.06). Median PFS was 7.5 mo (95% CI 3.4, 14.7) on R+Z and 4.6 mo (95% CI 3.2, 6.3) on R (p = 0.03). Median time to 1st SRE was 9.6 mo (95% CI 4.3, 15.5) on R+Z and 5.2 mo (95% CI 1.6-8.2) on R (p = 0.03). Conclusions: Addition of Z to R significantly reduced bone resorption markers in this RCC population of pts with the adverse prognostic feature of BM. Pts receiving R+Z had prolonged time to 1st SRE and PFS; larger studies are required to further evaluate the addition of bone-specific to targeted therapies in this disease. Clinical trial information: ACTRN12609000980235.

Histamine type 2 receptor antagonists as adjuvant treatment for resected colorectal cancer

BACKGROUND

Anecdotal reports of tumour regression with histamine type 2 receptor antagonists (H(2)RAs) have lead to a series of trials with this class of drug as adjuvant therapy to try and improve outcomes in patients with resected colorectal cancers. There was a plausible scientific rationale suggesting merit in this strategy. This included improved immune surveillance (by way of increasing tumour infiltrating lymphocytes), inhibiting the direct proliferative effect of histamine as a growth factor for colorectal cancer and, in the case of cimetidine, inhibiting endothelial expression of E-selectin (a cell adhesion molecule thought to be critical for metastatic spread).

OBJECTIVES

To determine if H(2)RAs improve overall survival when used as pre- and/or postoperative therapy in colorectal cancer patients who have had surgical resection with curative intent. We also stratified the results to see if there was an improvement in overall survival in terms of the specific H(2)RA used.

SEARCH METHODS

Randomised controlled trials were identified using a sensitive search strategy in the following databases: MEDLINE (1964 to present), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library 2009), EMBASE (1980 to present) and Cancerlit (1983 to present).

SELECTION CRITERIA

Criteria for study selection included: patients with colorectal cancer surgically resected with curative intent; H(2)RAs used i) at any dose, ii) for any length of time, iii) with any other treatment modality and iv) in the pre-, peri- or post-operative period. The results were stratified for the H(2)RA used.

DATA COLLECTION AND ANALYSIS

The literature search retrieved 142 articles. There were six studies included in the final analysis, published from 1995 to 2007, including a total of 1229 patients. All patients were analysed by intention to treat according to their initial allocation. Log hazard ratios and standard errors of treatment effects (on overall survival) were calculated using the Cochrane statistical package RevMan Version 5. Hazard ratios and standard errors were recorded from trial publications or, if not provided, were estimated from published actuarial survival curves using a spreadsheet designed for this purpose (http://www.biomedcentral.com/content/supplementary/1745-6215-8-16-S1.xls).

MAIN RESULTS

Of the six identified trials, five used cimetidine as the experimental H(2)RA, whereas one used ranitidine. There was a trend towards improved survival when H(2)RAs were utilised as adjuvant therapy in patients having curative-intent surgery for colorectal cancer (HR 0.70; 95% CI 0.48-1.03, P = 0.07). Analysis of the five cimetidine trials (n = 421) revealed a statistically significant improvement in overall survival (HR 0.53; 95% CI 0.32 to 0.87).

AUTHORS' CONCLUSIONS

Of the H(2)RAs evaluated cimetidine appears to confer a survival benefit when given as an adjunct to curative surgical resection of colorectal cancers. The trial designs were heterogeneous and adjuvant therapy has evolved since these trials were performed. Further prospective randomised studies are warranted.

RAD001 and zoledronic acid in renal cell carcinoma patients with bone metastases (RAZOR): A randomized phase II trial

e15054

Background: Bone metastases (BM) from renal cell carcinoma (RCC) are common, cause major morbidity and have been identified as an adverse prognostic feature. Previous trials have not assessed the effects of modern therapies on BM from RCC. Randomized data has demonstrated that zoledronic acid (ZOL) reduces skeletal-related-events (SRE’s) in RCC patients (pts). Bone turnover markers can identify pts at risk of SREs among those receiving ZOL. We sought to evaluate the effect on BM of RAD001 (everolimus) alone compared to RAD001 plus ZOL in the first-line setting. Methods: 30 treatment naïve pts with RCC and ≥ 1 BM were randomized 1:1 to RAD001 10mg daily (Arm A) vs. RAD001 + ZOL 4mg IV 4-weekly (dose adjusted for creatinine clearance [CrCl], Arm B). Key eligibility criteria were ECOG PS ≤ 2, no bisphosphonates or radiotherapy within 4 weeks and CrCl >35ml/min. Bone-specific assessments were performed at baseline, weeks 1,4,8 and12. Treatment was continued on the allocated arm until progression (RECIST 1.1). The primary objective was to assess the difference in bone turnover markers over the first 12-weeks. The primary endpoint was urine N-telopeptide (uNTX) levels with plasma C-telopeptide (CTX) being secondary. Secondary objectives include comparison of quality of life (QoL) and pain (FACT-BP, BPI scores), SREs, safety and efficacy (PFS, RR). Results: Heng prognostic group was poor, intermediate and favorable-risk in; 40.0%, 46.7%, 13.3% respectively in Arm A and 20.0%, 46.7%, 33.3% (Arm B). 53.3% (Arm A) and 60.0% (Arm B) of pts had prior nephrectomy. Over the first 12 weeks, the reduction in mean CTX on Arm B relative to Arm A was 77% (95% CI (68%, 83%); p<0.0001). Median PFS was 7.5mo (95% CI 3.5, 14.7) in Arm B and 5.5mo (95% CI 3.2, 7.2) in Arm A (p=0.11). Data on uNTX, QoL and SREs will be presented. At data cut off, 8 pts in Arm B had stopped ZOL before progression with either a drop in CrCl or hypocalcaemia. No cases of osteonecrosis of the jaw were seen. Conclusions: The addition of ZOL to RAD001 significantly reduced the bone resorption marker CTX in this treatment-naïve RCC population of pts with the adverse prognostic feature of BM.

Systematic review of histamine type 2 receptor antagonists as an adjunct to curative surgical resection in gastrointestinal malignancies

e15085

Background: H2RAs have induced regression in a number of malignancies. The mechanisms that may contribute to this effect include inhibition of T-suppressor lymphocytes, increased tumor infiltrating lymphocytes and blockade of histamine-induced tumor proliferation and angiogenesis. Unique to cimetidine is its ability to inhibit vascular endothelial expression of the cell adhesion molecule E-selectin, to which many GI tumor cells adhere via carbohydrate antigen ligands. The optimal use of H2RAs in cancer patients could therefore be as adjuvant therapy rather than for metastatic disease. Methods: This systematic review examines the impact of H2RAs on the overall survival of patients when used as an adjunct to curative surgical resection for a GI malignancy. Using a sensitive search strategy, randomized controlled trials were identified in relevant databases. Criteria for study selection included: patients with colorectal or gastric cancer surgically resected with curative intent; H2RAs used i) at any dose, ii) for any length of time, iii) with any other treatment modality and iv) in the pre-, peri- or post-operative period. The results were stratified for both the type of malignancy and the H2RA used and analyzed by meta-analysis using Cochrane Collaboration software. Results: Of 350 trials identified, 8 were eligible for inclusion and had sufficient data for analysis, including a total of 1461 patients. Meta-analysis revealed a risk ratio for mortality of 0.86 (95% CI 0.76–0.99, p = 0.03) for patients randomised to H2RAs. Trials of colorectal cancer patients where cimetidine was the H2RA being evaluated demonstrated a significant survival advantage, risk ratio 0.53 (95% CI 0.33–0.84, p = 0.007). All other subgroups demonstrated a non-significant trend favouring H2RAs. Conclusions: H2RAs, and cimetidine in particular, appear to confer a survival benefit when given as an adjunct to curative surgical resection of GI cancers. The trial designs were heterogeneous and further large studies are warranted.

No significant financial relationships to disclose.

Colorectal cancer survival following adjuvant chemotherapy with weekly i.v. fluorouracil 425 mg/m2 and folinic acid 50mg

e15089

Background: Adjuvant chemotherapy for colorectal cancer (CRC) using fluorouracil (5FU) and folinic acid (FA) has been proven effective and the QUASAR trial showed that a weekly administration schedule was as effective as, and less toxic than, the same daily doses delivered over 5 days every 4 weeks (the “Mayo regimen”). However the 5FU dose used (370 mg/m2) was lower than in some trials and a higher 5FU dose was considered desirable if tolerated. We therefore implemented a weekly regimen using 5FU 425 mg/m2 and DL-folinic acid 50mg in 2001 and retrospectively evaluated its efficacy and tolerability. Methods: Patients with non-metastatic CRC at assessment by medical oncologists in this institution between 2001 and 2004 were included in the analysis. Data was gathered on patient characteristics, duration of adjuvant chemotherapy and survival. Actuarial survival was calculated using the Kaplan-Meier method. Results: 417 patients (pts) were seen: 181 females, 236 males; median age 67 yrs (24–89); 291 with colon cancer, 126 with rectal cancer; 1 stage 1; 100 stage 2, 316 stage 3. Median follow-up was 6.2 years. 210 pts with colon cancer received adjuvant weekly 5FU/FA (32 stage 2, 178 stage 3) as did 58 pts with rectal cancer (50 of whom also received concurrent chemoradiation). 75% of pts with colon cancer received all 30 planned doses and 59% of rectal cancer pts received all 20 planned doses. 3 year survival for all pts treated with this regimen was 83.0% and for the subgroups with colon and rectal cancer it was 82.4% and 84.5% respectively. For stage 2 and 3 colon cancer pts treated with this regimen 3 year survival was 87.9% and 76.0% respectively; for stage III rectal cancer pts it was 84.1%. Conclusions: These outcomes compare favorably on indirect comparison with results from the QUASAR trial (which reported 3 year survival of 70.6%) and suggest that using a higher 5FU dose in this regimen is tolerable and may be advantageous.

No significant financial relationships to disclose.

The effects of sorafenib and sunitinib on bone turnover markers in patients with bone metastases from renal cell carcinoma

e16145

Background: Bone metastases (BM) from renal cell carcinoma (RCC) are common and associated with poor outcomes. While the multi-tyrosine kinase inhibitors (TKI's) sunitinib and sorafenib have advanced the treatment of metastatic RCC, their efficacy on BM is unknown. Urinary N-telopeptide (uNTX) is a marker of bone turnover measured in nmol/mmol creatinine. Elevated uNTX levels correlate with an increased risk of skeletal related events and mortality in patients receiving bisphosphonates for BM from a range of primaries. In this pilot biomarker study we sought to prospectively evaluate the effects on BM of these multi-TKI's in RCC patients. Methods: Eligible patients had advanced RCC, at least one BM evident on imaging and no bisphosphonate exposure within 4 weeks. UNTX levels (OsteoMark) were measured at; baseline and weeks-1, 4, 8 and 12 after commencing either sunitinib or sorafenib. The primary endpoint was the percentage change (Ch) in uNTX levels from baseline. Serum samples were also collected for KIT and VEGFR-2 (Quantikine). Patients also completed pain (including bone pain) and quality of life questionnaires. Results: The uNTX results on the first 9 patients are presented in the table below (7 received sunitinib and 2 sorafenib). In this group, sVEGFR-2 and sKIT levels fell by week-1 and 4 respectively and at week-12 the mean % changes (95% CI) were -34% (-0.53,-0.14) and -38% (-0.58,-0.18). Conclusions: In patients with BM from RCC and at least moderately elevated uNTX levels at baseline, these multi-TKI's show a significant trend to decrease uNTX levels, but perhaps not as effectively as bone-specific therapies (e.g. bisphosphonates) do in other malignancies. SVEGFR-2 and sKIT levels also fell across the patient group over the same period. This pilot data raises questions about the activity of the multi-TKI's in BM from RCC and further research is needed. [Table: see text]

[Table: see text]