A Phase I study of the safety, pharmacokinetics and efficacy of navitoclax plus docetaxel in patients with advanced solid tumors.

Aim: This Phase I study investigated safety of navitoclax and docetaxel in patients (n = 41) with advanced solid tumors. Patients & methods: Two navitoclax plus docetaxel dosing schedules (21 and 28 days) were evaluated. Maximum tolerated dose, dose-limiting toxicities and preliminary antitumor activity were assessed. Results: Ten (24%) patients experienced dose-limiting toxicities; dose-escalation cohorts: n = 7 (21-day schedule: n = 5; 28-day schedule: n = 2) and 21-day expanded safety cohort: n = 3. Navitoclax 150-mg days 1-5 every 21 days with docetaxel 75 mg/m2 day 1 was the maximum tolerated dose and optimal schedule. Adverse events included thrombocytopenia (63%), fatigue (61%), nausea (59%) and neutropenia (51%). Four confirmed partial responses occurred. Conclusion: Navitoclax 150-mg orally once/day was safely administered with docetaxel. Myelosuppression limited dose escalation; antitumor activity was observed. Clinical trial registration: NCT00888108 (ClinicalTrials.gov).

Pembrolizumab plus axitinib versus sunitinib monotherapy as first-line treatment of advanced renal cell carcinoma (KEYNOTE-426): extended follow-up from a randomised, open-label, phase 3 trial.

BACKGROUND: The first interim analysis of the KEYNOTE-426 study showed superior efficacy of pembrolizumab plus axitinib over sunitinib monotherapy in treatment-naive, advanced renal cell carcinoma. The exploratory analysis with extended follow-up reported here aims to assess long-term efficacy and safety of pembrolizumab plus axitinib versus sunitinib monotherapy in patients with advanced renal cell carcinoma. METHODS: In the ongoing, randomised, open-label, phase 3 KEYNOTE-426 study, adults (≥18 years old) with treatment-naive, advanced renal cell carcinoma with clear cell histology were enrolled in 129 sites (hospitals and cancer centres) across 16 countries. Patients were randomly assigned (1:1) to receive 200 mg pembrolizumab intravenously every 3 weeks for up to 35 cycles plus 5 mg axitinib orally twice daily or 50 mg sunitinib monotherapy orally once daily for 4 weeks per 6-week cycle. Randomisation was done using an interactive voice response system or integrated web response system, and was stratified by International Metastatic Renal Cell Carcinoma Database Consortium risk status and geographical region. Primary endpoints were overall survival and progression-free survival in the intention-to-treat population. Since the primary endpoints were met at the first interim analysis, updated data are reported with nominal p values. This study is registered with ClinicalTrials.gov, NCT02853331. FINDINGS: Between Oct 24, 2016, and Jan 24, 2018, 861 patients were randomly assigned to receive pembrolizumab plus axitinib (n=432) or sunitinib monotherapy (n=429). With a median follow-up of 30·6 months (IQR 27·2-34·2), continued clinical benefit was observed with pembrolizumab plus axitinib over sunitinib in terms of overall survival (median not reached with pembrolizumab and axitinib vs 35·7 months [95% CI 33·3-not reached] with sunitinib); hazard ratio [HR] 0·68 [95% CI 0·55-0·85], p=0·0003) and progression-free survival (median 15·4 months [12·7-18·9] vs 11·1 months [9·1-12·5]; 0·71 [0·60-0·84], p<0·0001). The most frequent (≥10% patients in either group) treatment-related grade 3 or worse adverse events were hypertension (95 [22%] of 429 patients in the pembrolizumab plus axitinib group vs 84 [20%] of 425 patients in the sunitinib group), alanine aminotransferase increase (54 [13%] vs 11 [3%]), and diarrhoea (46 [11%] vs 23 [5%]). No new treatment-related deaths were reported since the first interim analysis. INTERPRETATION: With extended study follow-up, results from KEYNOTE-426 show that pembrolizumab plus axitinib continues to have superior clinical outcomes over sunitinib. These results continue to support the first-line treatment with pembrolizumab plus axitinib as the standard of care of advanced renal cell carcinoma. FUNDING: Merck Sharp & Dohme Corp, a subsidiary of Merck & Co, Inc.

Phase 1/2a trial of intravenous BAL101553, a novel controller of the spindle assembly checkpoint, in advanced solid tumours.

BACKGROUND: BAL101553 (lisavanbulin), the lysine prodrug of BAL27862 (avanbulin), exhibits broad anti-proliferative activity in human cancer models refractory to clinically relevant microtubule-targeting agents. METHODS: This two-part, open-label, phase 1/2a study aimed to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of 2-h infusion of BAL101553 in adults with advanced or recurrent solid tumours. The MTD was determined using a modified accelerated titration design in phase I. Patients received BAL101553 at the MTD and at lower doses in the phase 2a expansion to characterise safety and efficacy and to determine the recommended phase 2 dose (RP2D). RESULTS: Seventy-three patients received BAL101553 at doses of 15-80 mg/m2 (phase 1, n = 24; phase 2a, n = 49). The MTD was 60 mg/m2; DLTs observed at doses ≥60 mg/m2 were reversible Grade 2-3 gait disturbance with Grade 2 peripheral sensory neuropathy. In phase 2a, asymptomatic myocardial injury was observed at doses ≥45 mg/m2. The RP2D for 2-h intravenous infusion was 30 mg/m2. The overall disease control rate was 26.3% in the efficacy population. CONCLUSIONS: The RP2D for 2-h infusion of BAL101553 was well tolerated. Dose-limiting neurological and myocardial side effects were consistent with the agent's vascular-disrupting properties. CLINICAL TRIAL REGISTRATION: EudraCT: 2010-024237-23.

Pharmacokinetics and safety of olaparib in patients with advanced solid tumours and mild or moderate hepatic impairment.

AIMS: Olaparib, a potent oral poly(ADP-ribose) polymerase inhibitor, is partially hepatically cleared. We investigated the pharmacokinetics (PK) and safety of olaparib in patients with mild or moderate hepatic impairment to provide dosing recommendations. METHODS: This Phase I open-label study assessed the PK, safety and tolerability of single doses of olaparib 300-mg tablets in patients with advanced solid tumours. Patients had normal hepatic function (NHF), or mild (MiHI; Child-Pugh class A) or moderate (MoHI; Child-Pugh class B) hepatic impairment. Blood was collected for PK assessments for 96 hours. Patients could continue taking olaparib 300 mg twice daily for long-term safety assessment. RESULTS: Thirty-one patients received ≥1 dose of olaparib and 30 were included in the PK assessment. Patients with MiHI had an area under the curve geometric least-squares mean (GLSmean) ratio of 1.15 (90% confidence interval 0.72, 1.83) and a GLSmean maximum plasma concentration ratio of 1.13 (0.82, 1.56) vs those with NHF. In patients with MoHI, GLSmean ratio for area under the curve was 1.08 (0.66, 1.74) and for maximum plasma concentration was 0.87 (0.63, 1.22) vs those with NHF. For patients with mild or moderate hepatic impairment, no new safety signals were detected. CONCLUSION: Patients with MiHI or MoHI had no clinically significant changes in exposure to olaparib compared with patients with NHF. The safety profile of olaparib did not differ from a clinically relevant extent between cohorts. No olaparib tablet or capsule dose reductions are required for patients with MiHI or MoHI.

Phase 1 dose-finding and pharmacokinetic study of eribulin-liposomal formulation in patients with solid tumours.

BACKGROUND: This phase 1 study examined the safety, tolerability, pharmacokinetics and preliminary efficacy of eribulin-liposomal formulation (eribulin-LF) in patients with advanced solid tumours. METHODS: Eligible patients with ECOG PS 0-1 were treated with eribulin-LF either on day 1 every 21 days (Schedule 1), or on days 1 and 15 every 28 days (Schedule 2). Doses ranged from 1.0 to 3.5 mg/m2, with dose escalation in a 3 + 3 design. The dose-expansion phase evaluated eribulin-LF in select tumour types. PRIMARY OBJECTIVES: maximum tolerated dose (MTD) and the recommended dose/schedule of eribulin-LF. RESULTS: Totally, 58 patients were enroled (median age = 62 years). The MTD was 1.4 mg/m2 (Schedule 1) or 1.5 mg/m2 (Schedule 2), the latter dose selected for the dose-expansion phase. Dose-limiting toxicity (DLTs) in Schedule 1: hypophosphatemia and increased transaminase levels. DLTs in Schedule 2: stomatitis, increased alanine aminotransferase, neutropenia and febrile neutropenia. The pharmacokinetic profile of eribulin-LF showed a similar half-life to that of eribulin (~30 h), but with a 5-fold greater maximum serum concentration and a 40-fold greater area-under-the-curve. Eribulin-LF demonstrated clinical activity with approximately 10% of patients in both schedules achieving partial responses. CONCLUSIONS: Eribulin-LF was well tolerated with a favourable pharmacokinetic profile. Preliminary evidence of clinical activity in solid tumours was observed.

A phase I study of intravenous and oral rucaparib in combination with chemotherapy in patients with advanced solid tumours.

BACKGROUND: This study evaluated safety, pharmacokinetics, and clinical activity of intravenous and oral rucaparib, a poly(ADP-ribose) polymerase inhibitor, combined with chemotherapy in patients with advanced solid tumours. METHODS: Initially, patients received escalating doses of intravenous rucaparib combined with carboplatin, carboplatin/paclitaxel, cisplatin/pemetrexed, or epirubicin/cyclophosphamide. Subsequently, the study was amended to focus on oral rucaparib (once daily, days 1-14) combined with carboplatin (day 1) in 21-day cycles. Dose-limiting toxicities (DLTs) were assessed in cycle 1 and safety in all cycles. RESULTS: Eighty-five patients were enrolled (22 breast, 15 ovarian/peritoneal, and 48 other primary cancers), with a median of three prior therapies (range, 1-7). Neutropenia (27.1%) and thrombocytopenia (18.8%) were the most common grade ⩾3 toxicities across combinations and were DLTs with the oral rucaparib/carboplatin combination. Maximum tolerated dose for the combination was 240 mg per day oral rucaparib and carboplatin area under the curve 5 mg ml-1 min-1. Oral rucaparib demonstrated dose-proportional kinetics, a long half-life (≈17 h), and good bioavailability (36%). Pharmacokinetics were unchanged by carboplatin coadministration. The rucaparib/carboplatin combination had radiologic antitumour activity, primarily in BRCA1- or BRCA2-mutated breast and ovarian/peritoneal cancers. CONCLUSIONS: Oral rucaparib can be safely combined with a clinically relevant dose of carboplatin in patients with advanced solid tumours (Trial registration ID: NCT01009190).

Phase I trials in patients with relapsed, advanced upper gastrointestinal carcinomas: experience in a specialist unit.

BACKGROUND: Conventional therapeutic options for patients with advanced upper gastrointestinal cancers (UGIC) are limited. Following first-line treatments, some patients are offered experimental therapies, including participation in Phase I trials. This study aims to describe the experience of UGIC patients treated in a dedicated Phase I unit. METHODS: Patient, tumour and treatment characteristics, and clinical outcomes of UGIC patients treated consecutively at the Drug Development Unit, Royal Marsden Hospital, between 2005 and 2009, were recorded. RESULTS: Ninety-six patients who previously received a median of 2 (range 1-4) lines of chemotherapies were treated in 30 Phase I trials. Of 81 evaluable patients, 9 achieved RECIST-objective response (11 %) with a 6-month clinical benefit rate of 14 %. Median progression free and overall survival were 7.7 weeks [95 %CI 7.7 (6.4-9.0)] and 19.1 weeks (95 %CI 17.5-20.8), respectively. Grade 3 or 4 toxicities were observed in 37 patients (39 %) and led to trial discontinuation in 9 (9 %); no toxicity-related death was recorded. In the multivariate analysis, serum albumin (<35 g/dl, HR2.0, p = 0.002) and lactate dehydrogenase (>192 µmol/l, HR1.7, p = 0.016) were prognostic of overall survival. CONCLUSION: Phase I clinical trials can be considered a reasonable option in selected patients with relapsed UGIC. The use of objective prognosticators may improve selection and risk/benefit profile of patients.

Secondary mutations in BRCA2 associated with clinical resistance to a PARP inhibitor.

PARP inhibitors (PARPi) for the treatment of BRCA1 or BRCA2 deficient tumours are currently the focus of seminal clinical trials exploiting the concept of synthetic lethality. Although clinical resistance to PARPi has been described, the mechanism underlying this has not been elucidated. Here, we investigate tumour material from patients who had developed resistance to the PARPi olaparib, subsequent to showing an initial clinical response. Massively parallel DNA sequencing of treatment-naive and post-olaparib treatment biopsies identified tumour-specific BRCA2 secondary mutations in olaparib-resistant metastases. These secondary mutations restored full-length BRCA2 protein, and most likely cause olaparib resistance by re-establishing BRCA2 function in the tumour cells.

Randomized Phase II trial of nintedanib, afatinib and sequential combination in castration-resistant prostate cancer.

AIMS: The aim of this article was to evaluate afatinib (BIBW 2992), an ErbB family blocker, and nintedanib (BIBF 1120), a triple angiokinase inhibitor, in castration-resistant prostate cancer patients. PATIENTS & METHODS: Patients were randomized to receive nintedanib (250 mg twice daily), afatinib (40 mg once daily [q.d.]), or alternating sequential 7-day nintedanib (250 mg twice daily) and afatinib (70 mg q.d. [Combi70]), which was reduced to 40 mg q.d. (Combi40) due to adverse events. The primary end point was progression-free rate at 12 weeks. RESULTS: Of the 85 patients treated 46, 20, 16 and three received nintedanib, afatinib, Combi40 and Combi70, respectively. At 12 weeks, the progression-free rate was 26% (seven out of 27 patients) for nintedanib, and 0% for afatinib and Combi40 groups. Two patients had a ≥50% decline in PSA (nintedanib and the Combi40 groups). The most common drug-related adverse events were diarrhea, nausea, vomiting and lethargy. CONCLUSION: Nintedanib and/or afatinib demonstrated limited anti-tumor activity in unselected advanced castration-resistant prostate cancer patients.

Pembrolizumab Plus Axitinib Versus Sunitinib as First-line Treatment of Advanced Renal Cell Carcinoma: 43-month Follow-up of the Phase 3 KEYNOTE-426 Study.

Previous analyses of KEYNOTE-426, an open-label, phase 3 randomized study, showed superior efficacy of first-line pembrolizumab plus axitinib to sunitinib in advanced clear cell renal cell carcinoma (ccRCC). We report results of the final protocol-prespecified analysis of KEYNOTE-426. Patients received pembrolizumab 200 mg intravenously every 3 wk plus axitinib 5 mg orally twice daily or sunitinib 50 mg orally once daily (4 wk per 6-wk cycle). The dual primary endpoints were overall survival (OS) and progression-free survival (PFS) as per RECIST v1.1 by a blinded independent central review. The secondary endpoints included objective response rate (ORR) and duration of response (DOR). The median study follow-up was 43 (range, 36-51) mo. Benefit with pembrolizumab plus axitinib versus sunitinib was maintained for OS (hazard ratio [HR], 0.73 [95% confidence interval {CI}, 0.60-0.88]), PFS (HR, 0.68 [95% CI, 0.58-0.80]), and ORR (60% vs 40%). The median DOR was 24 (range, 1.4+ to 43+) versus 15 (range, 2.3-43+) mo in the pembrolizumab plus axitinib versus the sunitinib arm. No new safety signals emerged. These results support pembrolizumab plus axitinib as a standard of care for patients with previously untreated advanced ccRCC. PATIENT SUMMARY: Extended results of KEYNOTE-426 support pembrolizumab plus axitinib as the standard of care for advanced clear cell renal cell carcinoma.

Targeting the DNA damage response in oncology: past, present and future perspectives.

PURPOSE OF REVIEW: The success of poly(ADP-ribose) polymerase inhibition in BRCA1 or BRCA2 deficient tumors as an anticancer strategy provided proof-of-concept for a synthetic lethality approach in oncology. There is therefore now active interest in expanding this approach to include other agents targeting the DNA damage response (DDR). We review lessons learnt from the development of inhibitors against DNA damage response mechanisms and envision the future of DNA repair inhibition in oncology. RECENT FINDINGS: Preclinical synthetic lethality screens may potentially identify the best combinations of DNA-damaging drugs with inhibitors of DNA repair and the DDR or two agents acting within the DDR. Efforts are currently being made to establish robust and cost-effective assays that may be implemented within appropriate time-scales in parallel with future clinical studies. Detection of relevant mutations in a high-throughput manner, such as with next-generation sequencing for genes implicated in homologous recombination, including BRCA1, BRCA2, and ataxia telangiectasia mutated is anticipated. Novel approaches targeting the DDR are currently being evaluated and inhibitors of ATM, RAD51 and DNA-dependent protein kinase are now in early drug discovery and development. SUMMARY: There remains great enthusiasm in oncology practice for pursuing the strategy of synthetic lethality. The future development of antitumor agents targeting the DDR should include detailed correlative biomarker work within early phase clinical studies wherever possible, with clear attempts to identify doses at which robust target modulation is observed.

FGF receptor inhibitors: role in cancer therapy.

The fibroblast growth factor (FGF) signaling pathway is implicated as a key driver of tumor progression and growth via the dysregulation of cell proliferation, differentiation, survival, and angiogenesis in multiple tumor types. In addition, it may serve as a mechanism of resistance to antivascular endothelial growth factor targeted therapy. As such this pathway has emerged as a relevant therapeutic target, and several agents that can inhibit or modulate its signaling are in various stages of development. This review will summarize the current clinical status of agents targeting FGF receptors. In addition, strategies to accelerate the clinical development of these targeted agents will be presented.

Outcomes of patients with metastatic melanoma treated with molecularly targeted agents in phase I clinical trials.

INTRODUCTION: First-line treatment options utilizing chemotherapy and cytokine-based treatments for patients with metastatic melanoma (MM) are unsatisfactory. We analyzed the clinical outcomes of patients with MM treated in phase I trials of novel agents. We hypothesized that patients included in phase I clinical trials did not have worse outcomes than with the chemotherapy and cytokine-based first-line treatment. METHODS: Data of patients with MM treated at The Drug Development Unit between 2004 and 2010 were collected. The response rate (RR) and time to progression (TTP) for first-line therapy were compared to those of phase I trial therapy. Patients acted as their own controls for statistical analyses. RESULTS: Sixty-five patients were treated in 31 phase I trials. First-line treatment included dacarbazine or temozolomide in 58 (89%) cases and interferon-α in 5 patients (8%) and cisplatin-based treatment in 2 patients (3%). There was no significant difference in either the RR (11 vs. 14%, p = 0.87) or TTP (90 vs. 53 days, p = 0.15) in patients treated with first-line treatment versus phase I treatment, respectively. CONCLUSION: Phase I clinical trials of molecularly targeted agents show clinical activity that is not dissimilar to that of treatment with existing chemotherapy and cytokine-based treatment.

Safety, pharmacokinetics, and preliminary activity of the anti-IGF-1R antibody figitumumab (CP-751,871) in patients with sarcoma and Ewing's sarcoma: a phase 1 expansion cohort study.

BACKGROUND: Figitumumab is a fully human IgG2 monoclonal antibody targeting the insulin-like growth-factor-1 receptor (IGF-1R). Preclinical data suggest a dependence on insulin-like growth-factor signalling for sarcoma subtypes, including Ewing's sarcoma, and early reports show antitumour activity of IGF-1R-targeting drugs in these diseases. METHODS: Between January, 2006, and August, 2008, patients with refractory, advanced sarcomas received figitumumab (20 mg/kg) in two single-stage expansion cohorts within a solid-tumour phase 1 trial. The first cohort (n=15) included patients with multiple sarcoma subtypes, age 18 years or older, and the second cohort (n=14) consisted of patients with refractory Ewing's sarcoma, age 9 years or older. The primary endpoint was to assess the safety and tolerability of figitumumab. Secondary endpoints included pharmacokinetic profiling and preliminary antitumour activity (best response by Response Evaluation Criteria in Solid Tumours [RECIST]) in evaluable patients who received at least one dose of medication. This study is registered with ClinicalTrials.gov, number NCT00474760. FINDINGS: 29 patients, 16 of whom had Ewing's sarcoma, were enrolled and received a total of 177 cycles of treatment (median 2, mean 6.1, range 1-24). Grade 3 deep venous thrombosis, grade 3 back pain, and grade 3 vomiting were each noted once in individual patients; one patient had grade 3 increases in aspartate aminotransferase and gammaglutamyltransferase concentrations. This patient also had grade 4 increases in alanine aminotransferase concentrations. The only other grade 4 adverse event was raised concentrations of uric acid, noted in one patient. Pharmacokinetics were comparable between patients with sarcoma and those with other solid tumours. 28 patients were assessed for response; two patients, both with Ewing's sarcoma, had objective responses (one complete response and one partial response) and eight patients had disease stabilisation (six with Ewing's sarcoma, one with synovial sarcoma, and one with fibrosarcoma) lasting 4 months or longer. INTERPRETATION: Figitumumab is well tolerated and has antitumour activity in Ewing's sarcoma, warranting further investigation in this disease. FUNDING: Pfizer Global Research and Development.

Pharmacokinetics and Safety of Olaparib in Patients with Advanced Solid Tumours and Renal Impairment.

BACKGROUND: Olaparib, a potent oral poly(ADP-ribose) polymerase inhibitor, is partially renally cleared. We investigated the pharmacokinetics and safety of olaparib in patients with mild or moderate renal impairment to provide dosing recommendations. METHODS: This phase I open-label study assessed the pharmacokinetics, safety and tolerability of single-dose, oral 300-mg olaparib tablets in adults (aged 18-75 years) with solid tumours. Patients had normal renal function, or mild or moderate renal impairment (estimated creatinine clearance ≥ 81, 51-80 or 31-50 mL/min, respectively). Blood was collected for 96 h, and urine samples collected for 24 h post-dose. Patients could continue taking olaparib 300 mg twice daily for a long-term safety assessment. RESULTS: Overall, 44 patients received one or more doses of olaparib and 38 were included in the pharmacokinetic assessment. Patients with mild renal impairment had an area under the curve geometric least-squares mean ratio of 1.24 (90% confidence interval 1.06-1.47) and a geometric least-squares mean maximum plasma concentration ratio of 1.15 (90% confidence interval 1.04-1.27) vs. those with normal renal function. In patients with moderate renal impairment, the geometric least-squares mean ratio for the area under the curve was 1.44 (90% confidence interval 1.10-1.89) and for the maximum plasma concentration was 1.26 (90% confidence interval 1.06-1.48) vs. those with normal renal function. No new safety signals were detected in patients with mild or moderate renal impairment. CONCLUSIONS: In patients with mild renal impairment, the small increase in exposure to olaparib was not considered clinically relevant. In patients with moderate renal impairment, exposure to olaparib increased by 44%; thus, these patients should be carefully monitored and the tablet dose should be adjusted to 200 mg twice daily. CLINICAL TRIALS REGISTRATION: NCT01894256.

Phase I dose escalation study of the anti insulin-like growth factor-I receptor monoclonal antibody CP-751,871 in patients with refractory solid tumors.

PURPOSE: This phase I study was undertaken to define the maximum tolerated dose, safety, and pharmacokinetic profile of CP-751,871. EXPERIMENTAL DESIGN: Using a rapid dose escalation design, patients with advanced nonhematologic malignancies were treated with CP-751,871 in four dose escalation cohorts. CP-751,871 was administered i.v. on day 1 of each 21-day cycle. Pharmacokinetic evaluation was done in all treatment cohorts during cycles 1 and 4. RESULTS: Twenty-four patients received 110 cycles at four dose levels. The maximum tolerated dose exceeded the maximal feasible dose of 20 mg/kg and, thus, was not identified. Treatment-related toxicities were generally mild. The most common adverse events were hyperglycemia, anorexia, nausea, elevated aspartate aminotransferase, elevated gamma-glutamyltransferase, diarrhea, hyperuracemia, and fatigue. At 20 mg/kg, 10 of 15 patients experienced stability of disease. Two of these patients experienced long-term stability. There were no objective responses. Pharmacokinetic analysis revealed a dose-dependent increase in CP-751,871 exposure and approximately 2-fold accumulation on repeated dosing in 21-day cycles. Plasma concentrations of CP-751,871 attained were several log-fold greater than the biologically active concentration. Treatment with CP-751,871 increased serum insulin and human growth hormone levels, with modest increases in serum glucose levels. CONCLUSIONS: CP-751,871 has a favorable safety profile and was well tolerated when given in continuous cycles. At the maximal feasible dose of 20 mg/kg, there was a moderate accumulation in plasma exposure, and most of the treated patients experienced stability of disease.

Pharmacokinetic Effects and Safety of Olaparib Administered with Endocrine Therapy: A Phase I Study in Patients with Advanced Solid Tumours.

INTRODUCTION: The PARP inhibitor olaparib is efficacious as monotherapy and has potential application in combination with endocrine therapy for the treatment of breast cancer. This phase I study assessed the safety and pharmacokinetic (PK) profiles of olaparib combined with tamoxifen, anastrozole or letrozole in patients with advanced solid tumours. METHODS: During part A, PK profiles were assessed in three consecutive treatment periods: (1) olaparib (tablet) 300 mg bid, days 1-5 followed by a 4-day washout; (2) cohort 1, tamoxifen 60 mg loading dose qd days 10-13, 20 mg qd days 14-26; cohort 2, anastrozole 1 mg qd days 10-19; cohort 3, letrozole 2.5 mg qd days 10-38; (3) as for period 2, with concomitant olaparib 300 mg bid for 5 days. Patients could then enter part B and receive olaparib monotherapy (300 mg bid continuously). Safety was assessed in parts A and B until 12 months after the last patient entered part B. RESULTS: Seventy-nine patients (20.3% with breast cancer) received treatment in part A; 72 completed part A and 69 entered part B. Anastrozole and letrozole had no effect on the PK profile of olaparib and vice versa. Co-administration with tamoxifen produced a modest decrease in exposure to olaparib [geometric least-squares mean (GLSmean) Cmax,ss and AUC0-τ decreased by 20% (90% CI 0.71-0.90) and 27% (0.63-0.84), respectively]. Exposure to tamoxifen was slightly increased when combined with olaparib [GLSmean Cmax,ss and AUC0-τ increased by 13% (1.06-1.22) and 16% (1.11-1.21), respectively]; however, the 90% CI fell within the 0.7-1.43 boundary and there were no changes in exposure to tamoxifen metabolites. The safety profile for olaparib alone and in combination with the antihormonal therapies was acceptable. CONCLUSIONS: The combination of olaparib and either anastrozole, letrozole or tamoxifen was generally well tolerated, with no clinically relevant PK interactions identified. FUNDING: AstraZeneca. CLINICAL TRIAL REGISTRATION: NCT02093351.

High frequency of radiological differential responses with poly(ADP-Ribose) polymerase (PARP) inhibitor therapy.

Despite impressive clinical activity in patients with germline BRCA1 and BRCA2 (BRCA1/2) mutant cancers, antitumor responses to poly(ADP-Ribose) polymerase (PARP) inhibitors are variable. We set out to assess the rate of intrapatient radiological differential responses (RDR) to PARP inhibitors, its correlation with patient outcomes, and the identification of factors associated with RDR. We retrospectively reviewed all patients with advanced cancers from five early phase PARP inhibitor monotherapy trials. 113 patients (ovarian cancers 57.5%; breast cancers 23.9%) were included in this retrospective study; 46 (40.7%) patients developed RDR on PARP inhibitor monotherapy. We identified two patterns of RDR: early RDR (1st or 2nd on-treatment scans) in 69.6% of patients, and late RDR (penultimate or final scans) in 30.4% of patients. Early RDR was associated with shorter time to progression (TTP) (225 vs 367 days, HR:0.59, 95%CI 0.36-0.98; p=0.04) and overall survival (OS) (499 vs 857 days; HR:0.47, 95%CI 0.27-0.82, p=0.006). Seventy-nine (69.9%) patients had known germline BRCA1/2 mutations; 49.4% of these BRCA1/2 mutation carriers developed RDR versus 20.6% of patients with unknown or wildtype BRCA1/2 status. Harboring germline BRCA1/2 mutations was independently predictive for RDR (RR:2.93, 95% CI 1.08-7.90, p=0.03). Patients with germline BRCA1 mutations had worse TTP and OS than BRCA2 mutation carriers (212 vs 406 days, HR:0.58, 95% CI 0.36-0.94, p=0.023 and 515 vs 937 days; HR:0.49, 95% CI 0.29-0.83; p=0.007). RDR with PARP inhibitors are frequent, particularly in germline BRCA1/2 mutation carriers. These findings have clinical implications for patient outcomes and may reflect underlying intrapatient genomic heterogeneity.

Clinical outcomes and prognostic factors of patients with advanced mesothelioma treated in a phase I clinical trials unit.

BACKGROUND: We have previously reported a prognostic score for patients in phase I trials in the Drug Development Unit, treated at the Royal Marsden Hospital (RPS). The RPS is an objective tool used in patient selection for phase I trials based on albumin, number of disease sites and LDH. Patients with mesothelioma are often selected for phase I trials as the disease remains localised for long periods of time. We have now reviewed the clinical outcomes of patients with relapsed malignant mesothelioma (MM) and propose a specific mesothelioma prognostic score (m-RPS) that can help identify patients who are most likely to benefit from early referral. METHODS: Patients who participated in 38 phase I trials between September 2003 and November 2015 were included in the analysis. Efficacy was assessed by response rate, median overall survival (OS) and progression-free survival (PFS). Univariate (UVA) and multivariate analyses (MVA) were carried out to develop the m-RPS. RESULTS: A total of 65 patients with advanced MM were included in this retrospective study. The PFS was 2.5 months (95% confidence interval [CI] 2.0-3.1 months) and OS was 8 months (95% CI 5.6-9.8 months). A total of four (6%) patients had RECIST partial responses, whereas 26 (40%) patients had RECIST stable disease >3 months. The m-RPS was developed comprising of three different prognostic factors: a neutrophil: lymphocyte ratio greater than 3, the presence of more than two disease sites (including lymph nodes as a single site of disease) and albumin levels less than 35 from the MVA. Patients each received a score of 1 for the presence of each factor. Patients in group A (m-RPS 0-1; n = 35) had a median OS of 13.4 months (95% CI 8.5-21.6), whereas those in group B (m-RPS 2-3; n = 30) had a median OS of 4.0 months (95% CI 2.9-7.1, P < 0.0001). A total of 56 (86%) patients experienced G1-2 toxicities, whereas reversible G3-4 toxicities were observed in 18 (28%) patients. Only 10 (15%) patients discontinued phase I trials due to toxicity. CONCLUSIONS: Phase I clinical trial therapies were well tolerated with early signals of antitumour activity in advanced MM patients. The m-RPS is a useful tool to assess MM patient suitability for phase I trials and should now be prospectively validated.