Here is a fun thing about biotech stocks: sometimes a company announces data that looks, on its face, quite good, and the stock goes down anyway. That is roughly what happened to Black Diamond Therapeutics Inc. (BDTX) on Tuesday.
The company reported updated Phase 2 data for silevertinib, its targeted cancer candidate, and laid out the regulatory next steps after a pivotal meeting with the U.S. Food and Drug Administration. The drug is being tested in frontline non-small cell lung cancer patients carrying non-classical EGFR mutations, which is a mouthful, but the numbers are the part that matters.
In the 43-patient intention-to-treat group receiving 200 mg daily, silevertinib achieved a 60% overall response rate, a 93% disease control rate, and median progression-free survival of 15.0 months, with no new safety signals. At the data cutoff, 18 patients remained on therapy.
Strong Central Nervous System Activity
Then there is the brain. Among 16 patients with untreated brain metastases, the drug posted an 86% central nervous system overall response rate and 12.2 months of systemic median progression-free survival. Patients without brain metastases achieved 23.5 months of median progression-free survival, with zero patients experiencing brain progression.
Black Diamond continues enrolling Cohort 4 to evaluate frontline patients at the planned pivotal 150 mg daily dose.
Phase 3 Clinical Roadmap And FDA Alignment
Following an End of Phase 2 meeting on Oct. 1, 2026, the FDA supported Black Diamond's Phase 3 program for treatment-naïve patients with non-classical EGFR mutations. Regulators outlined pathways for potential accelerated approval based on central nervous system response rates and full approval tied to progression-free survival.
Black Diamond plans to initiate the global Phase 3 registrational trial in the second quarter of 2027. The study will randomize 300 patients with untreated brain metastases against osimertinib or afatinib, alongside cohorts without brain metastases and patients with leptomeningeal disease.
Meanwhile, the company dosed its first patient in a Phase 2 glioblastoma trial, targeting interim data in early 2028.
Cash Runway Into Second Half Of 2028
Black Diamond closed the third quarter with $102.0 million in cash, cash equivalents, and investments, compared to $128.7 million at year-end 2025. Operating cash burn totaled $8.3 million for the quarter. The company expects existing liquidity will fund operations into the second half of 2028.
BDTX Price Action: Black Diamond Therapeutic shares were down 13.49% at $1.91 at the time of publication on Tuesday, according to market data.
