Key points from article :
Biotech company Boundless Bio is making major changes after early clinical results revealed safety concerns with its lead cancer drug. The company’s phase 1/2 trial of BBI-355, aimed at treating oncogene-amplified solid tumours, showed that while the drug demonstrated some antitumor activity, it also caused harmful blood-related side effects at those same doses. As a result, Boundless has abandoned plans to develop the drug as a standalone treatment.
The San Diego-based firm also shelved its other lead candidate, BBI-825, after earlier trials showed inconsistent drug exposure. Attempts to pair BBI-355 with existing cancer drugs like erlotinib and futibatinib didn’t yield better outcomes due to poor tolerance. Now, Boundless is pivoting to test BBI-355 and BBI-825 in combination, citing promising lab results showing the duo may work better together without overlapping toxic effects.
To stretch its budget, Boundless has laid off 33% of its workforce, reducing its staff to 64 and extending its financial runway into early 2028. The company is also advancing a new drug candidate, BBI-940, from its kinesin degrader program, with plans to begin human testing in 2026. Despite setbacks, Boundless is pressing forward with hopes that its new strategy will lead to safer, more effective cancer treatments.
