An experimental Roche drug is part of a high-profile new cancer immunotherapy Failure One of the two main targets of the pivotal test for lung cancer. The disappointing results come less than two months after the drug tiragolumab failed a separate phase 3 test in aggressive lung cancer that had spread.
The Roche drug is an antibody designed to bind to and block TIGIT, a so-called checkpoint protein that prevents immune cells from attacking cancer cells. Hope to stop it offers a new way to prime the immune system to fight cancer, and several big pharma companies have struck deals to join the TIGIT chase. But Roche’s latest failure with tiragolumab has raised questions about the drug and TIGIT’s target.
Roche has been testing tiragolumab in combination with the company’s already approved blockbuster cancer immunotherapy Tecentriq. Tecentriq is also a checkpoint inhibitor, but it targets PD-L1, a protein found abundantly on the surface of some cancer cells. The drug’s approved indications include non-small cell lung cancer and small cell lung cancer. By combining tiragolumab and Tecentriq to block two checkpoint proteins, Roche aims to overcome cancer’s ability to suppress the immune system and provide a way to restore the immune response.
Preliminary data released Wednesday came from a phase 3 study testing tiragolumab as a treatment for advanced non-small cell lung cancer that has spread and cannot be removed by surgery. The study enrolled 534 patients randomly assigned to receive tiragolumab plus Tecentriq or placebo and Tecentriq.
According to Roche, the combination of checkpoint inhibitors did not help patients live longer without their cancer getting worse, one of the two main goals of the phase 3 study. With the first analysis, Roche said it was too early to determine whether the drug met the study’s second main goal of improving patients’ overall survival. Nonetheless, the company noted improvements in both measures.
Levi Garraway, chief medical officer and head of global product development at Roche, said in a prepared statement: “While these results were not what we had hoped for in our first analysis, we look forward to seeing overall survival mature from this study. Looking forward to determine next steps.”
Despite the disappointing early results, Roche said the study will continue until the next planned analysis. So far, the drug has been well tolerated by patients and no new safety signals have been reported. Roche plans to conduct further analysis of the data at an upcoming medical meeting.
Tiragolumab’s clinical trial failure in March was in a phase 3 study testing the anti-TIGIT drug in combination with Tecentriq as a first-line treatment for extensive-stage small-cell lung cancer. Roche reported at the time that the drug missed its goal of progression-free survival, one of the two primary goals of the phase 3 study. In an earlier interim analysis, tiragolumab missed another primary goal of overall survival.
The potential of TIGIT inhibitors to expand the scope of cancer immunotherapy has already attracted the interest of several pharmaceutical companies. nearly a year ago, Bristol Myers Squibb pays $200 million upfront for global rights to Agenus’ TIGIT-blocking drug, AGEN1777. soon, GlaxoSmithKline joins TIGIT chase in $625M alliance with iTeos Therapeutics and its early TIGIT-targeted drug EOS-448. Gilead Sciences is looking for TIGIT through an alliance with Arcus Biosciences.Gilead paid Arcus $725 million last fall exercise option Two TIGIT-blocking antibodies are included in the clinical-stage program of three of its partners.
A clinical trial failure of Roche’s anti-TIGIT drug is affecting investors’ perceptions of other drug classes. Shares of Iteos fell more than 30% on Wednesday; shares of Arcus fell more than 29%.
Photo: Giuseppe Aresu/Bloomberg via Getty Images
