Scemblix® (asciminib) is approved in USA for the treatment of chronic myeloid leukemia

Date:2021-10-30 Views: 439 Times

Basel, October 29, 2021

Novartis announced today that the US Food and Drug Administration (FDA) approved Scemblix® (asciminib) for the treatment of chronic myeloid leukemia (CML) in two distinct indications.

The FDA granted Scemblix accelerated approval for adult patients with Philadelphia chromosome-positive CML in chronic phase (Ph+ CML-CP) previously treated with two or more tyrosine kinase inhibitors (TKIs), based on major molecular response (MMR) rate at 24 weeks; and full approval for adult patients with Ph+ CML-CP with the T315I mutation.

In accordance with the Accelerated Approval Program, continued approval for the first indication may be contingent upon verification and description of clinical benefit from confirmatory evidence. Scemblix is the first FDA-approved CML treatment that works by binding to the ABL myristoyl pocketand represents an important development for patients who experience resistance and/or intolerance to currently available TKI therapies. Also known as a STAMP inhibitor in scientific literature, Scemblix is being studied across multiple treatment lines for CML-CP, including the ASC4FIRST Phase III study evaluating Scemblix as a first-line treatment.

For many patients, current treatment for CML may be limited by intolerance or resistance, and sequential use of available TKIs is associated with increased failure rates. In an analysis of patients with CML treated with two prior TKIs, approximately 55% reported intolerance to previous treatment. Additionally, a pooled analysis in the second-line setting showed that up to 70% of patients are unable to achieve major molecular response (MMR) within two years of follow-up. Moreover, patients who develop the T315I mutation are resistant to most available TKIs, leaving them at an increased risk of disease progression.

The FDA approval of Scemblix is based on results from the Phase III ASCEMBL trial and a Phase I (NCT02081378) study that included patients with Ph+ CML-CP with the T315I mutation.

In patients with Ph+ CML-CP who had experienced resistance or intolerance to at least two TKIs, the ASCEMBL trial showed that:

  • Scemblix nearly doubled the MMR rate vs. Bosulif® (bosutinib)* at 24 weeks (25% vs. 13% [P=0.029])
  • The proportion of patients who discontinued treatment due to adverse reactions was more than three times lower in the Scemblix arm (n = 156) vs. patients in the Bosulif arm (n = 76) (7% vs. 25%)
  • The most common (incidence ≥ 20%) adverse reactions and laboratory abnormalities in the Scemblix arm were, respectively: upper respiratory tract infections and musculoskeletal pain; decrease in platelet and neutrophil counts, decrease in hemoglobin; increase in triglycerides, creatine kinase and alanine aminotransferase (ALT)