Novartis Scemblix FDA Approved in Newly Diagnosed CML, Offering Superior Efficacy & Favorable Safety & Tolerability Profile

Novartis recently announced Scemblix (asciminib) was granted accelerated approval by the US FDA for adult patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase (Ph+ CML-CP).

The accelerated approval is based on major molecular response rate (MMR) at week 48 from the ASC4FIRST Phase III trial that compared once daily Scemblix to all other investigator-selected (IS) standard of care (SoC) tyrosine kinase inhibitors (TKIs) (imatinib, nilotinib, dasatinib, and bosutinib). In the study, Scemblix demonstrated superior MMR rates in both primary endpoints at week 48 vs. IS SoC TKIs and imatinib alone. Continued approval for the newly diagnosed indication may be contingent upon verification and description of clinical benefit from confirmatory evidence.

The expanded indication in Ph+ CML-CP increases the population eligible for Scemblix by approximately four times, including newly diagnosed and previously treated adults. Newly diagnosed patients will now have access to a treatment that has shown superior efficacy vs. all standard of care therapies and a favorable safety and tolerability profile.

“Many patients who are newly diagnosed with CML struggle to navigate this chronic condition and may switch or even stop treatment because of side effects that interrupt their daily lives,” said Lee Greenberger, PhD, Chief Scientific Officer at The Leukemia & Lymphoma Society. “That’s why approvals of new first-line treatment options are so important. For patients, finding a medicine that’s right for them at the very beginning of treatment may lead to better long-term disease control with fewer side effects.”

While TKIs have transformed CML into a chronic disease, efficacy and safety challenges continue to hinder long-term treatment success for many patients. Many newly diagnosed patients do not meet molecular response goals, and many discontinue or change treatment due to intolerance. Nearly half of CML patients do not meet efficacy milestones (MMR) and almost one in four patients discontinue or switch treatment within one year.

“While there are a range of effective TKIs currently available for newly diagnosed patients, clinicians frequently have had to weigh sacrificing either efficacy or tolerability,” said Jorge Cortes, MD, Director, Georgia Cancer Center. “In the first-of-its-kind ASC4FIRST trial, Scemblix achieved impressive results across all three parameters of efficacy, safety and tolerability versus all standard of care TKIs. This Scemblix data has the potential to be practice-changing.”

The FDA approval of Scemblix is based on results from the Phase III ASC4FIRST trial in patients newly diagnosed with Ph+ CML-CP. Data showed:

Nearly 20% more patients treated with Scemblix achieved MMR vs. IS SoC TKIs (imatinib, nilotinib, dasatinib and bosutinib) (68% vs. 49%, < 0.001) and nearly 30% more patients achieved MMR vs. imatinib alone (69% vs. 40%, < 0.001) at week 48.

Scemblix is the first CML treatment to show superior efficacy along with a favorable safety and tolerability profile vs. imatinib and second generation TKIs, with fewer treatment-related grade ≥3 ARs (25.5% vs. 33% and 42%), dose reductions (6% vs. 14% and 24%), and half the rate of ARs leading to treatment discontinuation (4.5% vs. 11% and 9.8%).

Patients treated with Scemblix also achieved deeper rates of molecular responses including MR4 compared with IS-TKIs and imatinib alone (41% vs. 22% and 16%) by week 48.

In newly diagnosed patients, the safety profile was consistent with previous registration studies with no new safety concerns observed. The most common ARs (≥ 20%) were musculoskeletal pain, rash, fatigue, upper respiratory tract infection, headache, abdominal pain and diarrhea.

The ASC4FIRST trial remains ongoing, with the next scheduled analysis at week 96 to evaluate the key secondary endpoint (MMR at week 96) and additional secondary endpoints.

The approval was also supported by preliminary data from the Phase 2 ASC2ESCALATE study, which includes Ph+ CML-CP patients who have been previously treated with one prior TKI with discontinuation due to treatment failure, warning, or intolerance. Data will be shared at a future medical meeting.

“We are proud to help redefine CML treatment once again with Scemblix, as we continue to deliver on our 20+ year commitment to innovation and support in CML,” said Victor Bulto, President US, Novartis. “Despite many advances in the field, patients still need treatment options that are highly effective with a favorable tolerability profile to help enable them to achieve meaningful outcomes as they manage chronic conditions. With this approval, we can offer newly diagnosed adult Ph+ CML-CP patients a new treatment option that combines both, with the potential to change the trajectory of many more people living with CML.”

ASC4FIRST (NCT04971226) is a Phase III, head-to-head, multi-center, open-label, randomized study of oral Scemblix 80 mg QD vs. IS first- or second-generation TKIs (imatinib, nilotinib, dasatinib or bosutinib) in 405 adult patients with newly diagnosed Ph+ CML-CP. The two primary endpoints of the study are to compare efficacy of asciminib vs. IS SoC TKIs and to compare efficacy vs. that of TKI within the stratum of participants with imatinib as pre-randomization selected TKI, based on proportion of patients that achieve MMR at week 48.

The study remains ongoing with key secondary endpoints of proportion of patients that achieve MMR at week 96 and a safety endpoint of discontinuation of study treatment due to an AE (TTDAE) by week 96. The study also assesses additional secondary safety and efficacy endpoints, including MMR, MR4, MR4.5, complete hematological response (CHR) and BCR::ABL1 ≤1% at and by all scheduled data collection time points; duration of and time to first MMR, MR4 and MR4.5; time to treatment failure; event-free survival, failure-free survival, progression-free survival and overall survival.

Scemblix is the first CML treatment that works by Specifically Targeting the ABL Myristoyl Pocket (referred to as a STAMP inhibitor in scientific literature). The current approved CML treatments are TKIs that target the ATP-binding site (ATP-competitive).

Scemblix was granted accelerated approval in the US to treat newly diagnosed adults and is also approved for previously treated adult patients with Ph+ CML-CP. Scemblix received Breakthrough Therapy designation for the treatment of newly diagnosed adult patients and was reviewed under the FDA’s Real-Time Oncology Review (RTOR) program. It is approved in more than 75 countries, including the EU, to treat those who have previously been treated with two or more TKIs with Ph+ CML-CP. In some countries, including the US, Scemblix is also approved in patients with Ph+ CML-CP with the T315I mutation.

Scemblix is being studied across multiple treatment lines for Ph+ CML-CP, both as a monotherapy and in combination.

Novartis, with its 20+ year history in CML, is committed to continuing to address areas of unmet patient need and reducing barriers to patient access and affordability that prevent patients from benefiting from innovation. Novartis Patient Support is available to help guide eligible patients through the various aspects of getting started on treatment including help understanding insurance coverage and identifying potential financial assistance options. Patients or providers can call 866-433-8000 or visit support.scemblix.com to learn more.

Novartis has a long-standing scientific commitment to patients living with CML. For more than two decades, our bold science has helped transform CML from a life-limiting condition for many patients. Despite these advancements, there’s still work to be done. We continue to research ways to target the disease more selectively and to address the challenges of not reaching treatment efficacy goals, experiencing treatment resistance and/or intolerance that many patients face. Our legacy inspires our future innovation – we continue to lead the way in developing novel medicines to address serious unmet needs in CML. Our commitment also goes beyond science. Our 20+ year collaboration with the Max Foundation has provided access to Gleevec (imatinib), Tasigna (nilotinib) and now Scemblix and is delivering tremendous patient impact in low- and middle-income countries, with over 100,000 patients supported to date.