Asciminib (Scemblix)

How Medicare covers it

Part D (forms used at home). Part A during a covered inpatient stay. No Part B clinician-administered form in the CMS Part B spending file.

What it treats

Philadelphia chromosome-positive chronic myeloid leukemia (Ph+ CML) in chronic phase (CP) in adults — newly diagnosed, previously treated, and Ph+ CML in CP with the T315I mutation. The newly diagnosed use is approved under accelerated approval based on major molecular response rate. Brand name Scemblix.

What it is for, in depth

Scemblix (asciminib) treats a blood cancer called Philadelphia chromosome-positive chronic myeloid leukemia, or Ph+ CML, while it is in its early chronic phase. It is for adults who are newly diagnosed, adults who have already been treated before, and adults whose leukemia has a specific change called the T315I mutation, which can make other drugs stop working. For most patients it is taken as 80 mg once a day or 40 mg twice a day, while patients with the T315I mutation take a higher dose of 200 mg twice a day, always on an empty stomach. It comes as film-coated tablets in three strengths: 20 mg, 40 mg, and 100 mg. Treatment keeps going as long as it is helping and the side effects stay manageable.

How it works

It is an ABL/BCR-ABL1 tyrosine kinase inhibitor. It blocks the ABL1 kinase activity of the BCR::ABL1 fusion protein by binding to the ABL myristoyl pocket, and it showed activity against wild-type BCR::ABL1 and several mutant forms, including the T315I mutation.

How it is taken

Tablets taken by mouth without food — avoid food for at least 2 hours before and 1 hour after a dose — and swallowed whole (do not break, crush, or chew). For newly diagnosed or previously treated Ph+ CML in CP: 80 mg once a day at about the same time each day, or 40 mg twice a day about 12 hours apart. For Ph+ CML in CP with the T315I mutation: 200 mg twice a day. Treatment continues as long as there is clinical benefit or until side effects become unacceptable. If a once-daily dose is missed by more than about 12 hours (or a twice-daily dose by more than about 6 hours), skip it and take the next dose as scheduled.

Common side effects

The most common side effects (20% or more) were muscle, bone and joint pain (musculoskeletal pain and arthralgia), rash, fatigue, upper respiratory tract infection, headache, belly pain, and diarrhea. Common lab changes that got worse in 20% or more of patients included lower lymphocyte, white blood cell, platelet and neutrophil counts, lower corrected calcium and hemoglobin, and higher lipase, cholesterol, uric acid, ALT, alkaline phosphatase, and triglycerides.

Serious warnings

Warnings include low blood counts (myelosuppression — thrombocytopenia, neutropenia, and anemia, with blood counts checked every 2 weeks for the first 3 months and monthly after that), pancreatic toxicity including pancreatitis (lipase and amylase checked monthly), high blood pressure, hypersensitivity reactions (rash, swelling, bronchospasm), cardiovascular toxicity including ischemic heart and brain conditions, blood clots, cardiac failure, arrhythmia and QTc prolongation, and harm to an unborn baby (embryo-fetal toxicity). The label lists no contraindications.

Who should be careful

People with a history of pancreatitis need closer monitoring of lipase and amylase. People with cardiovascular risk factors should be watched for cardiovascular signs and symptoms. Females who could become pregnant must have their pregnancy status checked before starting, use effective contraception during treatment and for 1 week after the last dose, and not breastfeed during treatment and for 1 week after the last dose; the drug may impair fertility in females.

Major interactions

Strong CYP3A4 inhibitors raise asciminib levels (watch closely for side effects at the 200 mg twice-daily dose), strong CYP3A4 inducers lower its levels, and itraconazole oral solution containing hydroxypropyl-beta-cyclodextrin lowers asciminib levels and should be avoided at all doses. Asciminib itself raises levels of certain CYP3A4 substrates, CYP2C9 substrates, P-gp substrates, and BCRP substrates such as rosuvastatin, so those drugs may need close monitoring or dose changes, and some combinations should be avoided at the 200 mg twice-daily dose.

Cost and saving notes

This drug is usually covered under Medicare Part D, often through a specialty pharmacy with prior authorization. If your cost is high, ask your plan about a tier exception. If you have limited income, the Extra Help (Low-Income Subsidy) program can lower your Part D premiums and drug costs. In 2027, your total yearly out-of-pocket spending on Part D drugs is capped at $2,400, and you can ask your plan to spread those costs out in monthly payments through the Medicare Prescription Payment Plan. The maker may also offer a patient support program.

Why it is in its tier

Asciminib (Scemblix) sits on Tier 5 in 96.91% of the plans that list it (5325 of 5495 listing plans). Tier 5 is the specialty tier — instead of a flat copay, patients usually pay a percentage of the drug's cost (coinsurance), which is why specialty drugs feel expensive even with coverage. The data-visible drivers: It is a brand-only product with no generic version in the formulary data, and the CMS dashboard puts its average Part D spending at about $150,066 per beneficiary for 2024 — among the highest-cost drugs in the program, which matches where plans place it. It is listed by 100.0% of Part D plans. The tier shown is the most common one; individual plans vary.

Sources

• SCEMBLIX (ASCIMINIB) TABLET, FILM COATED [NOVARTIS PHARMACEUTICALS CORPORATION] — DailyMed
• MedlinePlus — National Library of Medicine
• MedlinePlus — Asciminib

What official patient guides say

Asciminib is a tablet you take by mouth once a day, or twice a day about twelve hours apart, at around the same time or times every day. Timing around food matters: take it on an empty stomach, keeping the window around meals that your care team sets for you. Swallow the tablets whole — do not split, chew, or crush them. Treatment continues over time, and your doctor may adjust your dose or pause or stop treatment depending on how you respond and how you are feeling, so keep taking it even if you feel well and do not stop on your own. If you miss a dose, the rule depends on your schedule: once-daily users who are more than twelve hours late, and twice-daily users who are more than six hours late, should skip that dose and resume on schedule — never double up. Store the tablets in their original container, tightly closed, at room temperature away from heat and moisture, and keep your lab appointments; you may also be asked to check your blood pressure at home.

Source: MedlinePlus — Asciminib

Part D formulary coverage

Source: CMS Prescription Drug Plan Formulary, Pharmacy Network, and Pricing Information Files — Monthly file 2026-10-15 (plan year 2027), file 2027_20261008.zip (data.cms.gov dataset ed1496ea-23e7-41f1-9292-172fa842ccfb): basic drugs formulary file + plan information file, both dated 20261031 inside the zip; downloaded and aggregated 2026-10-30. Medication RxCUI sets resolved through the NLM RxNav (RxNorm) API.

What you pay

A tier is not a price; what you pay depends on your plan, pharmacy, and benefit stage; Extra Help or Medicaid can lower it further.

Sources: CMS Plan Benefit Package + formulary data; CMS NADAC · Checked 2026-11-07

Coverage by plan and tier

Of the 5,495 Medicare drug plans we track for 2027, 5,495 list Asciminib (Scemblix) — 100% of plans. Most of those plans put it on Tier 5: 5,325 plans, 96.9% of the plans that list it. Other plans place it on Tier 1 (123 plans), Tier 4 (46 plans) or Tier 2 (1 plans). For example: Aetna Medicare Dual Extra (HMO D-SNP) puts it on Tier 5; Aetna Medicare Dual Extra Care (PPO D-SNP) puts it on Tier 5; Aetna Medicare Value Plus (PPO) puts it on Tier 5. You can compare these plans side by side on our Medicare Advantage hub. A tier is not a price. What you pay also depends on whether you have met your plan';s deductible, whether the drug costs a flat copay or a share of the price, and whether you get Extra Help or Medicaid.

Read next

• Part D in 2027: The $700 Deductible, the $2,400 Cap, and the $35 Insulin Rule
• Extra Help in 2027: Lower Drug Copays and Who Qualifies
• Checking Medicare Savings Programs and Extra Help

Part D spending averages (2024)

Source: CMS Medicare Part D Spending by Drug (Drug Spending Dashboard), release RY26 P04 V10, data through 2024 (DSD_PTD_RY26_P04_V10_DY24_BGM.csv), downloaded 2026-10-30

Companies covering this drug

Part D and Medicare Advantage plan sponsors that list this drug on a formulary, 50 at a time.