Hamid, Omid

9009 Background: Programmed death-1 (PD-1) is an inhibitory T-cell co-receptor that may lead to suppression of antitumor immunity. Lambrolizumab is a humanized monoclonal IgG4 antibody against PD-1. This study explored the safety and clinical activity of lambrolizumab in patients (pts) with advanced melanoma (MEL). Methods: In this ongoing phase 1b expansion study of MEL pts with or without previous ipilimumab (IPI) treatment, lambrolizumab was administered IV every 2 or 3 weeks until disease progression or unacceptable toxicity. Tumor response was assessed every 12 weeks by independent, central, blinded radiographic review per immune-related response criteria and RECIST 1.1. Results: As of December 1, 2012, 294 pts with MEL were enrolled, including 179 IPI-naive and 115 IPI-pretreated. Pts received lambrolizumab 10 mg/kg (n = 183) or 2 mg/kg (n = 111). Preliminary data from the first 85 consecutive pts dosed before April 25, 2012, who had independent radiologic review available as of December 3, 2012, indicate a confirmed overall response rate per RECIST 1.1 of greater than 35%, pooled across all doses and schedules and including both IPI-naive and IPI-pretreated patients. The median duration of response has not been reached as only 2 pts who had initial response discontinued due to disease progression, but the duration of confirmed responses range from 28+ to 240+ days (up to 8+ months). Among 133 pts who were dosed with lambrolizumab before July 31, 2012, and evaluable for adverse events (AEs) as of September 28, 2012, fatigue (22%), rash (18%), and pruritus (14%) were the most common drug-related AEs (mostly grade 1/2). The incidence of drug-related grade 3/4 AEs was 10% (24% regardless of attribution). Four drug-related cases of pneumonitis were reported, all of grade 1/2. Grade 3/4 drug-related hypothyroidism (n = 1) and hyperthyroidism (n = 1) were noted. Conclusions: Preliminary data suggest that lambrolizumab has significant antitumor activity and is well tolerated with manageable side effects in both IPI-naive and IPI-pretreated MEL pts. These data have led to an ongoing, international, randomized study of lambrolizumab versus chemotherapy in IPI-pretreated MEL. Clinical trial information: NCT01295827.

9005 Background: Dual inhibition of the MAP kinase (MAPK) pathway with dabrafenib (D) and trametinib (T) in combination has demonstrated clinical benefit compared to D alone in a randomized Phase II trial in V600 BRAF-mutant MM pts, thus delaying the development of BRAFi resistance. Little is known about the efficacy of D + T after BRAFi resistance has been acquired. This analysis evaluates the ability of D + T combination to treat acquired resistance compared to the D + T combination as first-line treatment. Methods: These data from a phase I/II study include 1. BRAFi-resistant group: pts who received 150/2 D+T in Part B (n=26) and Part C (n=43) following progression on BRAFi monotherapy (mono); 2. BRAFi-naïve group: pts who received initial 150/2 D+T in Part B (n=24) and Part C (n=54). Results: Baseline characteristics (ECOG PS, M staging, LDH) were similar across all groups.In the Part B BRAFi-resistant group, 93% of pts previously received D or vemurafenib and all pts received D prior to D+T in Part C. In BRAFi-resistant group, prior best response of CR/PR (38%, 56%), SD (35%, 27%), PD (27%, 7%) was observed in Parts B and C respectively. In BRAFi-resistant group, the ORR and PFS with D+T was lower than initial D+T in BRAFi-naive group. Median duration of response (DoR) in BRAFi-resistant group cannot be calculated due to small no. of pts responding. Median DoR for BRAFi-naïve pts was 11.3 mo and 10.5 mo in Parts B and C respectively. In Part C, the 12-mo overall survival rates in BRAFi-naïve (150/2) pts was 79% vs 70% for pts initially on D mono, despite 80% pts crossing over to D+T combination. Conclusions: The clinical activity for 150/2 D+T combination is consistently superior in BRAFi-naive group vs BRAFi-resistant group in both Parts B and C. Dual MAPK blockade can delay clinical resistance to BRAF inhibition. However, once BRAFi resistance has occurred, the combination of BRAFi + MEKi is far less effective. Clinical trial information: NCT01072175. [Table: see text]

2510 Background: Blocking the interaction between programmed death-1 (PD-1), a co-inhibitory receptor expressed by activated T cells, and its ligand PD-L1 may enhance T-cell function. Here we describe the safety and activity from the first clinical study of BMS-936559 in patients (pts) with advanced solid tumors, further validating the importance of the PD-1/PD-L1 pathway as a target for cancer therapy. Methods: BMS-936559 was given Q2 wk IV in a 6-wk cycle at doses of 0.3−10.0 mg/kg during dose escalation and/or cohort expansion; pts could receive up to 16 cycles (48 doses). Results: As of August 1, 2011, 162 pts with melanoma (MEL, n=53), non-small-cell lung (NSCLC, n=50), colorectal (n=18), renal cell (RCC, n=17), ovarian (n=17), and pancreatic (n=7) cancer were treated. Median therapy duration was 11 wks (max 99 wks). Common related adverse events (rAEs; ≥5% pts) included fatigue, diarrhea, infusion reaction, arthralgia, rash, and pruritus. The incidence of grade 3-4 rAEs was 8.6%. AEs of special interest included hypothyroidism, hepatitis, sarcoidosis, endophthalmitis, and myasthenia gravis; there were no drug-related deaths. Clinical activity was observed in MEL, RCC, and NSCLC. Objective responses (ORs; RECIST 1.0) were observed in heavily pretreated pts. ORs were durable; among 16 pts with ORs, 7 had responses lasting ≥1 yr. Two other pts had ongoing ORs with durations of 2.3 and 8.5 mo at data lock. Several pts had prolonged stable disease. Some pts had a persistent reduction in overall tumor burden in the presence of new lesions but were not categorized as responders. In NSCLC, ORs were observed irrespective of histology. Conclusions: BMS-936559 was active and generally well tolerated in pts with NSCLC, RCC, and MEL. In conjunction with data from anti-PD-1/BMS-936558 trials, this study concurrently validates the importance of the PD-1/PD-L1 pathway for cancer immunotherapy and supports further clinical development of anti-PD-1/PD-L1 directed therapy. [Table: see text]

Objectives: Immunotherapy (IO) has become standard of care (SOC) for many advanced malignancies, although identifying patients likely to benefit remains difficult. We sought to assess whether demographic factors are associated with response to IO, compared with SOC systemic therapy, using stratified meta-analysis. Methods: A systematic review of MEDLINE, PubMed, Embase, and Scopus from inception to October 2, 2018. Randomized controlled trials comparing IO to SOC in patients with advanced solid organ malignancies were included if results were stratified by age, performance status (PS), or race, assessing overall survival (OS). Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for each group using random-effects models independently. Results: We identified 21 eligible randomized controlled trials, including 20 stratified by age, 17 by PS, and 4 by race. Patients with PS 0 (HR, 0.74; 95% CI, 0.63-0.86) and PS≥1 (HR, 0.75; 95% CI, 0.68-0.83) had similar OS benefits from IO compared with SOC (P=0.80). There was no difference on the basis of patient race (white vs. nonwhite) (P=0.46). IO demonstrated an OS benefit for younger (below 65 y: HR, 0.73; 95% CI, 0.65-0.82) and older (65 y and above: HR, 0.79; 95% CI, 0.71-0.88) patients with no difference between age groups (P=0.27). Among prespecified subgroup analyses, there was significant effect modification in 2 subgroups: younger patients in the first-line setting (P=0.03) and those receiving anti-CTLA-4 drugs (P=0.05). Conclusions: When examining OS using stratified meta-analysis, we did not demonstrate significant differences in IO efficacy according to patient age, PS or race, though data on race were sparse.