Novartis Achieves 144-Week Superiority Data for Scemblix in Newly Diagnosed CML Across All TKI Comparators

Sustained efficacy data extending to nearly three years positions Novartis for potential label expansion of Scemblix (asciminib) in newly diagnosed Ph+ CML-CP, a development that carries direct implications for CMC submissions, commercial-scale process validation, and long-term demand planning across its oncology manufacturing network.

Week-144 results from the pivotal ASC4FIRST trial, presented at the 2026 ASCO Annual Meeting, showed Scemblix achieving a major molecular response (MMR) rate of 77.1% versus 53.4% for investigator-selected standard-of-care TKIs overall. Against imatinib alone, the MMR gap widened to 32 percentage points (79.2% vs. 47.1%). Against second-generation TKIs, nilotinib, dasatinib, and bosutinib, Scemblix delivered a 15.2% higher MMR rate (75.0% vs. 59.8%; unadjusted nominal p=0.01, descriptive). Deeper molecular responses at MR4 and MR4.5 thresholds also favored Scemblix across all comparator strata.

The tolerability profile reinforces the efficacy picture. Fewer grade ≥3 adverse events were observed with Scemblix versus both imatinib and 2G TKIs, and the discontinuation rate due to adverse events was less than half that of comparators. On-treatment retention at week 144 reached 78.6% for Scemblix versus 55.9% for all SoC TKIs, a gap that signals durable patient adherence and, for supply planners, a more predictable long-term demand curve than shorter-duration therapies typically generate.

For QA and regulatory leads, the dataset now spans primary and key secondary endpoints met at weeks 48, 96, and 144, providing a longitudinal evidence base that supports regulatory dossier updates under ICH Q10-aligned lifecycle management frameworks. Any supplemental NDA or label variation filing triggered by these data would require Novartis to demonstrate that existing validated processes and control strategies remain fit for purpose at commercial scale, particularly if expanded indication language drives volume increases beyond current batch-size parameters.

The ASC4FIRST trial enrolled adult patients with newly diagnosed Philadelphia chromosome-positive CML in chronic phase, randomized across pre-selected imatinib (n=203) and 2G TKI (n=202) strata. Secondary objectives were not powered for statistical significance; the 15.2% MMR advantage versus 2G TKIs carries a nominal p-value for descriptive purposes only.

The 144-week retention and response trajectory will serve as a measurable benchmark against which any future label variation submission, and the manufacturing scale commitments that accompany it, will be evaluated.

Source: Novartis via GlobeNewswire, June 1, 2026. Data presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting.