FDA Approves Atezolizumab Monotherapy in Advanced PD-L1-High NSCLC

The FDA has granted approval to atezolizumab (Tecentriq) monotherapy as treatment for adults with metastatic non–small cell lung cancer (NSCLC) whose tumors have high PD-L1 expression (PD-L1 staining on ≥50% of tumor cells [TC ≥50%] or PD-L1 staining on tumor-infiltrating immune cells [IC] covering ≥10% of the tumor area [IC ≥10%]), as determined by an FDA-approved test, and have no EGFR or ALK genomic tumor aberrations. This approval marks the fifth indication for atezolizumab in metastatic NSCLC and lung cancer in general, Genentech announced in a press release.¹

“We are pleased to offer people with certain types of lung cancer a new chemotherapy-free option that can help prolong their lives and be administered on a flexible dosing schedule, including an option for once-a-month Tecentriq infusions,” said Levi Garraway, MD, PhD, chief medical officer and head of Global Product Development, Genentech, in a statement. “Today marks the fifth approval of Tecentriq in lung cancer, as we remain committed to providing an effective and tailored treatment option for every person diagnosed with this disease.”

Data from the phase III IMpower110 study served as the basis for this approval after showing an overall survival (OS) benefit when compared with chemotherapy among patients with high PD-L1 expression (TC3/IC3) and EGFR/ALK wild-type disease. The median OS was 20.2 with atezolizumab versus 13.1 months with chemotherapy, (HR, 0.59, 95% CI, 0.40-0.89; P = .0106) at a median follow-up of 15.7 months.^1,2

Atezolizumab also led to a favorable progression-free survival (PFS) of 8.1 months (95% CI, 6.8-11.0) compared with 5.0 months (95% CI, 4.2-5.7) in the chemotherapy arm (HR, 0.63; 95% CI, 0.45-0.88; P = .007). Among patients with high PD-L1 expression, there was a confirmed overall response rate (ORR) of 38.3% with atezolizumab and 28.6% with chemotherapy. The median duration of response was not reached with atezolizumab and was 6.7 months with chemotherapy.²

In terms of safety, atezolizumab demonstrated a safety profile consistent with prior reports of the PD-1 inhibitor. No new safety signals were observed with the drug. Treatment-related adverse events that were grade 3 or 4 occurred in 12.9% of patients in the atezolizumab arm versus 44.1% in the chemotherapy arm.

The randomized, open-label, IMpower110 study divided 554 patients in a 1:1 fashion to receive 1200 mg of atezolizumab monotherapy or chemotherapy consisting of cisplatin or carboplatin plus either pemetrexed for patients with nonsquamous NSCLC or gemcitabine for patients with squamous NSCLC. Participants in the chemotherapy arm were also given pemetrexed as maintenance therapy for nonsquamous NSCLC or best supportive care for squamous NSCLC. Atezolizumab was administered every 21 days until disease progression, unacceptable toxicity, or death. Patients also received chemotherapy in 21-day cycles.

Using the SP142 assay, patients were also divided into PD-L1 expression level subgroups and evaluated for efficacy and safety. The primary end point was OS and the secondary end points included investigator-assessed PFS, ORR, and DOR.

The total study population included 572 patients, 555 of whom had wild-type disease.

In addition to its multiple indications in NSCLC, atezolizumab is being explored as a treatment for patients with genitourinary cancers, skin cancers, breast cancer, gastrointestinal cancers, gynecological cancers, and head and neck cancers, in phase III clinical trials.¹

_References:

_{1. FDA approves Genentech’s tecentriq as a first-line monotherapy for certain people with metastatic non-small cell lung cancer [news release]. San Francisco, California: Genentech; May 18,2020. https://bit.ly/2ZfNjHK. Accessed May 18, 2020.}

_{2. Spigel DR, De Marinis F, Giaccone G, et al. IMpower110: interim overall survival (OS) analysis of a Phase III study of atezolizumab (atezo) vs platinum-based chemotherapy (chemo) as first-line (1L) treatment (tx) in PD-L1-selected NSCLC. Ann Oncol. 2019;30(suppl_5):v851-v934. doi:10.1093/annonc/mdz394.}