Roche pioneered TIGIT immunotherapy drugs following Keytruda's success. Early trials showed promise with a 31% response rate versus 16% for placebo. Pharmaceutical companies rushed to develop similar treatments, investing billions in what appeared to be the next breakthrough in cancer therapy.

Roche launched an ambitious "SKYSCRAPER" program with 12 concurrent trials covering 5,000 patients. The first Phase 3 results missed progression-free survival endpoints. While initially dismissed as specific to small-cell lung cancer, subsequent trials in more treatable lung cancers also failed.

In November 2024, Roche reported that its flagship trial missed the overall survival endpoint as well. The $625 million upfront payment from GSK and other substantial investments now appear premature. The TIGIT story mirrors amyloid-beta Alzheimer's drug disappointments, showing the complex path from lab results to effective therapies.