Enliven Therapeutics announces positive Phase 1 CML data and FDA alignment for Phase 3

What happened

Enliven Therapeutics presented updated Phase 1 data for ELVN-001 in CML, showing 61% overall MMR and 48% MMR by 24 weeks in the 80 mg QD cohort, with 67% overall MMR in patients with 1-2 prior TKIs. The company also announced FDA alignment on 80 mg QD as the recommended Phase 3 dose and on the 2L+ patient population for the ENABLE-2 pivotal trial, which is expected to initiate in the second half of 2026. While the data appear supportive, the median treatment duration of 35 weeks and 161 patients enrolled still represent early-stage follow-up, leaving questions about late safety and durability beyond 8 months. The FDA alignment de-risks the Phase 3 design but does not guarantee successful enrollment or eventual regulatory approval. Our thesis remains cautious, as the stock at $42 already prices in a smooth execution, and the key variables of long-term safety and Phase 3 initiation timing remain unconfirmed.

Implication

The Phase 1 data and FDA alignment are positive but expected, and the stock's current valuation reflects a high probability of successful Phase 3 start. Investors should note that the data remain early-stage, with follow-up extending to only ~35 weeks; late safety signals or enrollment delays could still undermine the thesis. The FDA alignment removes a key regulatory uncertainty but does not guarantee trial execution speed or eventual data quality. We maintain a WAIT rating with conviction 3.5, and we would become more constructive only upon observable Phase 3 initiation artifacts or longer-term durability data. Near-term, the news may drive a short-term rally, but given insider selling and reliance on a single asset, we advise caution at current levels.

Thesis delta

The FDA alignment on Phase 3 dose and population removes a key design uncertainty, modestly supporting the base case scenario. However, the overall thesis shift is limited, as the market already anticipated this alignment, and the core risks of follow-up safety and Phase 3 execution remain unchanged. We see no compelling reason to upgrade from WAIT until we see evidence of clinical durability beyond 8 months or tangible Phase 3 start milestones.