Tipifarnib in Head and Neck Squamous Cell Carcinoma With HRAS Mutations

Mutations in the HRAS (mHRAS) proto-oncogene occur in 4%-8% of patients with recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC). Tipifarnib is a farnesyltransferase inhibitor that disrupts HRAS function. We evaluated the efficacy of tipifarnib in patients with R/M mHRAS HNSCC.

Lurbinectedin (LUR) in combination with Irinotecan (IRI) in patients (pts) with advanced solid tumors: Updated results from a phase Ib-II trial

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Background: LUR is a novel agent that exerts antitumor activity through inhibition of trans-activated transcription and modulation of tumor microenvironment. Preclinical synergism/additivity in combination with IRI has been reported, thus prompting the conduct of this clinical trial. Methods: Phase Ib-II trial to evaluate escalating doses of LUR on Day (D) 1 plus a fixed dose of IRI 75 mg/m2 on D1 and D8 every 3 weeks (q3w) in pts with advanced solid tumors (+/- G-CSF, if dose-limiting toxicities [DLTs] were neutropenia). Starting dose was LUR 1.0 m/m2 + IRI 75 mg/m2. Results: 77 pts have been treated to date at 5 dose levels, 51 of them at the recommended dose (RD). Baseline characteristics of all 77 pts were: 48% females, 68% ECOG PS=1; median age 57 years (range, 19-75 years); median of 2 prior lines (range, 0−4 lines). The maximum tolerated dose (MTD) was LUR 2.4 mg/m2 + IRI 75 mg/m2 with G-CSF, and the RD was LUR 2.0 mg/m2 + IRI 75 mg/m2 with G-CSF. DLTs in Cycle 1 occurred in 2/3 evaluable pts at the MTD and 3/13 evaluable pts at the RD, and comprised omission of IRI D8 infusion due to grade (G) 3/4 neutropenia (n=3 pts) or G2-4 thrombocytopenia (n=2). At the RD (n=51), common G1/2 non-hematological toxicities were nausea, vomiting, fatigue, diarrhea, anorexia and neuropathy. G3 non-hematological toxicities (diarrhea 10%, fatigue 10%) and G3/4 hematological abnormalities (neutropenia 49%, thrombocytopenia 10%) were transient. Conclusions: The combination of LUR and IRI had acceptable tolerance, with no unexpected toxicities. Transient myelosuppression was dose-limiting. The RD is LUR 2.0 mg/m2 on D1 + IRI 75 mg/m2 on D1 and D8 q3w with G-CSF. Antitumor activity was observed at the RD in SCLC pts, as well as in endometrial carcinoma pts. Hints of activity were also observed in STS pts. Updated results will be presented. Clinical trial information: NCT02611024 . [Table: see text]

Two-year follow-up of bintrafusp alfa, a bifunctional fusion protein targeting TGF-β and PD-L1, for second-line (2L) treatment of non-small cell lung cancer (NSCLC)

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Background: Bintrafusp alfa (M7824) is a first-in-class bifunctional fusion protein composed of the extracellular domain of the TGF-βRII receptor (a TGF-β “trap”) fused to a human IgG1 mAb blocking PD-L1. Interim analysis of a global phase 1 study (NCT02517398) found an objective response rate (ORR) of 27.5% and a manageable safety profile in patients with NSCLC who received bintrafusp alfa 1200 mg in the 2L setting; median overall survival (OS) was not reached. Here we present the longest efficacy and safety follow-up in a cohort receiving bintrafusp alfa. Methods: Patients with advanced NSCLC unselected for PD-L1 expression level who progressed after first-line standard treatment (no prior immunotherapy) were randomized to receive bintrafusp alfa 500 or 1200 mg (n = 40 each) Q2W until disease progression, unacceptable toxicity or trial withdrawal. The primary objective was best overall response (BOR) per RECIST 1.1; secondary and exploratory objectives include safety and OS, respectively. Results: As of October 15, 2019, a total of 40 patients received bintrafusp alfa at the recommended phase 2 dose of 1200 mg Q2W for a median of 17 (range, 2-136) weeks, with a median follow-up of 128 weeks; 18 patients were still alive, 3 patients had an ongoing response, and 1 patient remained on treatment. Results for the 1200 mg dose cohort showed an ORR of 27.5%, and a median duration of response of 18 months. The 18- and 24-month progression-free survival and OS rates were 18.4% and 11.0%, and 49.7% and 39.7%, respectively. Duration of response rates at 18 and 24 months were 42.4% and 21.2%, respectively. Median OS in patients with positive (≥1%) PD-L1 expression was 21.7 months; 6 of 7 patients with high (≥80% with Ab clone 73-10, which is equivalent to ≥50% with 22C3) PD-L1 expression were still alive. The overall safety profile has remained consistent since the interim analysis, with no new safety signals or deaths and 1 additional treatment-related discontinuation (blood alkaline phosphatase increased). Conclusions: After two years of follow-up, bintrafusp alfa continues to show manageable safety with durable responses and encouraging long-term survival, especially in patients with high PD-L1 expression. A study evaluating bintrafusp alfa vs pembrolizumab as first-line treatment for NSCLC is ongoing in patients with high PD-L1 expression (NCT03631706). Clinical trial information: NCT02517398 .