NEW YORK – An inadvertent data disclosure forced Genentech on Wednesday to acknowledge non-small cell lung cancer patients' overall survival on the anti-TIGIT immunotherapy tiragolumab and the anti-PD-L1 agent Tecentriq (atezolizumab).
This data represents a second interim analysis within the Phase III SKYSCRAPER-01 trial in which Roche subsidiary Genentech is comparing the tiragolumab-Tecentriq combination against Tecentriq alone as a first-line therapy for patients with PD-L1-high locally advanced or metastatic NSCLC. While the overall survival data weren't mature as of the November 2022 data cutoff, investigators estimated a median overall survival of 22.9 months in the tiragolumab-Tecentriq arm versus 16.7 months in the Tecentriq arm at a median follow-up of 15.5 months. This translates to a 19 percent reduction in the risk of death for patients on the combination regimen. At the time of this second interim analysis, tiragolumab-Tecentriq was well tolerated, and researchers observed no new safety signals with the addition of tiragolumab to Tecentriq.
In the SKYSCRAPER-01 trial, Genentech is tracking two primary endpoints: progression-free survival and overall survival. In an interim analysis the firm conducted in May 2022, the combination therapy failed to meet the progression-free survival endpoint. At that time, the median progression-free survival was numerically better in the tiragolumab-Tecentriq arm compared to the Tecentriq arm, but the degree of improvement in the combination arm wasn't statistically significant.
Despite this, Roche did not give up on the program and said it would continue the trial until the next planned interim analysis. Since in the first interim analysis the median overall survival was also numerically higher, the firm also said it would await the final overall survival readout.
Tiragolumab is designed to block TIGIT receptors on immune cells from binding to the poliovirus receptor on tumor cells, an interaction that allows cancer cells to evade an immune system attack. Roche is hoping tiragolumab will work synergistically with Tecentriq to benefit patients with high-PD-L1 expression. Roche began the SKYSCRAPER-01 study after observing that patients with PD-L1-high NSCLC had the most benefit from the drug combo in the CITYSCAPE study.