Sandeep H. Mashru

PURPOSE The irreversible ErbB family tyrosine kinase inhibitor (TKI) afatinib plus the EGFR monoclonal antibody cetuximab was previously shown to overcome resistance to EGFR TKIs. We studied whether the combination of afatinib plus cetuximab compared with afatinib alone would improve progression-free survival (PFS) in patients with treatment-naive EGFR-mutant non–small-cell lung cancer (NSCLC) by preventing or delaying resistance. METHODS Patients with EGFR-mutant NSCLC without prior treatment of advanced disease were enrolled in this phase II, multicenter trial and randomly assigned to receive afatinib 40 mg orally daily plus cetuximab 500 mg/m 2 intravenously every 2 weeks or afatinib alone. The primary end point was PFS. RESULTS Between March 25, 2015 and April 23, 2018, 174 patients were randomly assigned, and 168 (83 on afatinib + cetuximab and 85 on afatinib) were eligible. There was no improvement in PFS in patients receiving afatinib plus cetuximab compared with afatinib alone (hazard ratio [HR], 1.01; 95% CI, 0.72 to 1.43; P = .94; median, 11.9 months v 13.4 months). Similarly, there was no difference in response rate (67% v 74%; P = .38) or overall survival (HR, 0.82; 95% CI, 0.50 to 1.36; P = .44). Toxicity was greater with the combination: grade ≥ 3 adverse events related to treatment occurred in 72% of patients receiving afatinib plus cetuximab compared with 40% of those receiving afatinib alone, most commonly rash and diarrhea. Dose reductions were more common in patients receiving the combination, and 30% of patients in this arm discontinued cetuximab due to toxicity. At interim analysis, there was insufficient evidence to support continued accrual, and the trial was closed. CONCLUSIONS The addition of cetuximab to afatinib did not improve outcomes in previously untreated EGFR-mutant NSCLC, despite recognized activity in the acquired resistance setting.

Importance: The prognosis for patients with glioblastoma is poor following standard therapy with surgical resection, radiation, temozolomide, and tumor-treating fields. Objectives: To evaluate the combination of veliparib and temozolomide in glioblastoma based on preclinical data demonstrating significant chemosensitizing effects of the polyadenosine diphosphate-ribose polymerase 1/2 inhibitor veliparib when combined with temozolomide. Design, Setting, and Participants: Patients with newly diagnosed glioblastoma with MGMT promoter hypermethylation who had completed concomitant radiation and temozolomide were enrolled between December 15, 2014, and December 15, 2018, in this Alliance for Clinical Trials in Oncology trial. The data for this analysis were locked on April 21, 2023. Interventions: Patients were randomized and treated with standard adjuvant temozolomide (150-200 mg/m2 orally, days 1-5) combined with either placebo or veliparib (40 mg orally, twice daily, days 1-7) for 6 cycles. Main Outcomes and Measures: The primary end point for the phase 3 portion of the trial was overall survival (OS). Results: There were 322 patients randomized during the phase 2 accrual period and an additional 125 patients randomized to complete the phase 3 accrual, for a total of 447 patients in the final phase 3 analysis. The median (range) age for patients was 60 (20-85) years and 190 patients (42.5%) were female. The median OS was 24.8 months (90% CI, 22.6-27.7) for the placebo arm and 28.1 months (90% CI, 24.3-33.3) for the veliparib arm (P = .17). The difference in survival did not meet the prespecified efficacy end point. However, there was a separation of the survival curves that favored the veliparib arm over 24 to 48 months of follow-up. The experimental combination was well tolerated with an acceptable elevation in grade 3 or 4 hematologic toxic effects. Conclusions and Relevance: This trial found that adding veliparib to adjuvant temozolomide did not significantly extend OS in patients with newly diagnosed, MGMT-hypermethylated glioblastoma. Trial Registration: ClinicalTrials.gov Identifier: NCT02152982.

2001 Background: PolyADP-ribose polymerase (PARP) is an important modulator of DNA repair following temozolomide (TMZ) therapy. Pre-clinical testing demonstrated significant survival benefit for the combination of TMZ and PARP inhibitor veliparib in a subset of GBM pt-derived xenografts with MGMT promoter hypermethylation. Methods: After central pathology review and MGMT testing, patients (pts) with newly diagnosed, MGMT promoter hypermethylated GBM who had completed concurrent radiation and TMZ were randomized to adjuvant therapy with TMZ (Days 1-5 q28 days) combined with either placebo or veliparib (Days 1-7 q28 days). Veliparib/placebo+TMZ treatment was continued for up to 6 cycles. Pts accrued on the phase II and III portions of the trial were included in the primary endpoint analysis of overall survival (OS), with 90% power to detect a hazard ratio of 0.71 using a one-sided log-rank test with type I error rate of 0.05. The planned phase III sample size was 400 pts with data maturity after 302 deaths. Results: The phase II and III portions of the trial were open to accrual from 12/15/2014 to 2/6/2017 and 11/8/2017 to 10/15/2018, respectively; 447 pts were accrued to the trial and used in this intention to treat analysis. The two treatment groups were well balanced for prognostic factors, 421 pts initiated treatment, median follow-up was 57.8 months (mos), 380 pts had disease progression and 335 pts have died. There was no difference in OS (p = 0.15; HR 0.89 (0.71-1.11), median OS 28.1 vs. 24.8 mo. for TMZ+veliparib vs. TMZ+placebo, respectively) and no difference in secondary endpoint progression free survival (PFS, p = 0.31; HR 1.05 (0.86-1.30), median 13.2 vs. 12.1 mo, respectively). There was a notable trend for extended OS with TMZ+veliparib treatment at intermediate time-points between 24 and 42 mos (3-year OS 36.6% vs. 28.9% with TMZ+placebo, p = 0.09). In an unplanned exploratory analysis, treatment with TMZ at the time of first recurrence was associated with extended post-recurrence OS (p = 0.03) for pts treated on the experimental arm; median post-recurrence OS with TMZ salvage was 17.0 mo in the TMZ+veliparib arm and 12.6 mo in the TMZ+placebo arm, as compared to 9.6 mo in either arm if TMZ salvage was not used. These data are consistent with a possible effect of veliparib limiting the emergence of TMZ resistance in a subset of GBM pts. Conclusions: Veliparib combined with adjuvant TMZ therapy was not associated with significant extension in OS or PFS in newly diagnosed, MGMT hypermethylated GBM pts. However, a subset of pts treated with TMZ+veliparib may have an extended survival following re-treatment with TMZ at first recurrence. Clinical trial information: NCT02152982.