Terns Pharmaceuticals Inc. (TERN) just took its best shot at one of the major players in leukemia treatment, and the data suggests they might have landed a solid punch.

The small biotech presented updated results Monday from its ongoing CARDINAL trial testing TERN-701 in chronic myeloid leukemia patients at the American Society of Hematology Annual Meeting and Exposition. The headline numbers? Pretty compelling for a drug taking on Novartis AG's (NVS) established franchise.

The Numbers That Matter

As of the September 13, 2025 data cutoff, 63 patients were enrolled in the trial. Among 38 patients who could be evaluated for efficacy, the overall major molecular response rate hit 74% by 24 weeks. Breaking that down further: 64% of patients achieved MMR for the first time, while 100% of those who already had MMR maintained it. Nobody lost their MMR by the data cutoff, which is exactly what you want to see.

The deep molecular response achievement rate reached 29% by 24 weeks. For context, that's the kind of deeper response that doctors really like to see in leukemia patients.

Safety Profile Looks Clean

Here's where things get interesting from a commercial perspective: 87% of patients remained on treatment as of the data cutoff. That's a strong retention rate. The drug showed no dose-limiting toxicities during dose escalation, and researchers never even hit a maximum tolerated dose. Most side effects were low grade with no apparent relationship to dosing levels.

The drug's exposure levels were roughly dose-proportional across the range tested, which makes pharmacology predictable and dosing straightforward.

Based on this profile and a 75% MMR achievement rate at doses of 320mg and above over 24 weeks, Terns selected 320mg and 500mg once daily as the recommended Phase 2 doses for expansion.

"We are particularly encouraged to see unprecedented rates of MMR in a highly refractory population, including compelling response achievement in patients with a lack of efficacy on prior asciminib, ponatinib, and/or other marketed and investigational TKIs," said Emil Kuriakose, Terns' chief medical officer.

The company emphasized that at the recommended Phase 2 dose range, they observed a 36% deep molecular response achievement rate by 24 weeks, demonstrating what they call fast response kinetics.

The Competition

Novartis (NVS) markets asciminib under the brand name Scemblix, a targeted therapy for adults with Philadelphia chromosome-positive chronic myeloid leukemia. That's the incumbent drug Terns is essentially trying to unseat.

"The safety profile and higher MMR achievement rate of 75% over 24 weeks at doses of 320mg and above support the selection of 320mg and 500mg QD as the recommended phase 2 doses for expansion," said Amy Burroughs, Terns' CEO, in Monday's press release.

Wall Street's Take

William Blair came out bullish on Tuesday, writing: "We believe TERN-701 is on track to challenge Scemblix's dominance and disrupt the treatment paradigm of CML, which has a global TAM of roughly $5 billion."

Analyst Andy Hsieh highlighted the efficacy perspective, noting particular excitement about the 64% MMR achievement rate. That number doubles what Scemblix and Enliven Therapeutics Inc.'s (ELVN) investigational ELVN-001 have reported in comparable disease settings, which came in around 24% to 32%.

"There were six additional efficacy evaluable patients included in the presentation as compared to the abstract, four of whom achieved MMR, and we believe the consistency of efficacy data adds to our bullish conviction," William Blair added.

Shares of Terns Pharma (TERN) were down 4.25% at $38.52 during premarket trading Tuesday, though that pullback after a major data presentation isn't uncommon as traders process the implications.