ISEMBYLD™ (apitegromab-mstn) for HCPs | SMA Treatment
Prescribing Information
Prescribing Information
For US healthcare professionals age 18 and older

NOW APPROVED

ISEMBYLD™ is the first and only FDA approved muscle-targeted treatment for SMA

For adults and pediatric patients 2 years of age and older with spinal muscular atrophy (SMA) who are currently receiving a survival motor neuron 2 (SMN2)-targeted treatment

Read the AnnouncementPatient Enrollment FormDosing Calculator
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Scholar Rock Supports™ offers personalized support for your patients’ ISEMBYLD journey

Scholar Rock Supports is designed to help your patients get access to ISEMBYLD and to provide support throughout the treatment experience.

Scholar Rock Supports includes Rx Onboarding and Care Coordinators (ROCCs), Case Managers, and a full suite of support programs.

The dedicated ROCCs can help patients and caregivers with:

•Navigating insurance
•Financial and copay assistance
(for eligible patients)
•Infusion day logistics
•Caregiver support
•Educational materials
•What to expect with ISEMBYLD

Scholar Rock Supports also provides coverage and reimbursement resources.

Download Patient Enrollment FormVisit Scholar Rock Supports website

To learn more, call Scholar Rock Supports at
1-833-777-5444
(1-833-SRRK-444)

Monday – Friday
8 AM – 8 PM ET

ISEMBYLD Dosing Calculator

The recommended dosage of ISEMBYLD is 10 mg/kg administered once every 4 weeks as an intravenous infusion over approximately 60 minutes to 120 minutes at an infusion rate no greater than 150 mL/hour.


Enter patient weight in kilograms to calculate total dose, total vials needed, total volume to withdraw, total saline volume, and total infusion volume. Vials are single-dose only. Unused ISEMBYLD should be discarded.1 Dose calculations based on 10 mg/kg.


Administration Instructions

  • If necessary, remove the diluted ISEMBYLD solution from the refrigerator and allow the diluted solution to warm to room temperature. Do not use external heat sources to warm ISEMBYLD diluted solution because heat may damage the product.
  • Visually inspect the diluted ISEMBYLD solution for particles or discoloration prior to administration [see Dosage Forms and Strengths (3)]. Do not use if it is discolored, opaque, or foreign particles are seen.
  • Use a dedicated line with an infusion set containing a 0.2 or 0.22 micron low protein binding polyethersulfone (PES) in-line infusion filter. Use infusion sets and lines that are di(2-ethylhexyl)phthalate (DEHP)-free.
  • Infuse the diluted solution of ISEMBYLD intravenously over approximately 60 minutes to 120 minutes at an infusion rate no greater than 150 mL/hour.
  • After completion of the infusion, flush the infusion line with 0.9% Sodium Chloride Injection to ensure that all the ISEMBYLD has been administered.
  • If a planned dose is missed, it is recommended to administer ISEMBYLD as soon as possible and then restart the dosing schedule 4 weeks after the missed dose is administered.
  • Alternatively, if a planned dose is missed, dosing may be resumed on the next scheduled dose to maintain the original dosing schedule.
Total Dose
Weight (kg) x Recommended dose (10 mg/kg)
Total Vials Needed
Total dose (mg) ÷ Amount of 1 vial (150 mg)
Total Volume to Withdraw
Total dose (mg) ÷ 50 mg/mL
Each mL contains 50 mg
Total Saline Volume
Total infusion volume (mL) - Total volume to withdraw (mL)
Total Infusion Volume
Total dose (mg) ÷ 5 mg/mL

Disclaimer: By using this dosing calculator, you agree to the following: This dosing calculator is intended for use by qualified healthcare providers only. The information provided is not a substitute for clinical judgment. Scholar Rock, Inc. makes no claims as to the accuracy of the information provided. All calculations should be confirmed prior to administration. Neither Scholar Rock, Inc. nor any party involved in the creation or publication of this website shall be liable to you or others for any actions taken or decisions made in reliance on the information provided by this dosing calculator. Please refer to the ISEMBYLD full Prescribing Information, which contains complete dosing and administration information.

Reference: 1. ISEMBYLD. Prescribing Information. Scholar Rock, Inc; 2026.

Indication and Important Safety Information

Indication & Important Safety Info

INDICATION

ISEMBYLD (apitegromab-mstn) is indicated for the treatment of spinal muscular atrophy (SMA) in adults and pediatric patients 2 years of age and older who are currently receiving a survival motor neuron 2 (SMN2)‑targeted treatment.

IMPORTANT SAFETY INFORMATION

WARNINGS AND PRECAUTIONS

Fractures

ISEMBYLD may increase the risk of fractures, including serious fractures. Use with caution in patients with a history of low bone density or multiple fractures. In patients who experience fractures, weigh the risks and benefits of continuing ISEMBYLD.

ADVERSE REACTIONS

The most common adverse reactions (incidence ≥20% of patients treated with ISEMBYLD and more frequent than placebo) were upper respiratory tract infections, vomiting, cough, other viral infections, headache, gastroenteritis, pharyngitis, and hypersensitivity.

USE IN SPECIFIC POPULATIONS

Pregnancy and Lactation

Based on animal data, ISEMBYLD may cause fetal harm. There are no adequate data on the developmental risk associated with the use of ISEMBYLD in pregnant women.

There are no data on the presence of ISEMBYLD in human milk, the effects on the breastfed infant, or the effects of the drug on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for ISEMBYLD, and any potential adverse effects on the breastfed infant.

Females and Males of Reproductive Potential

Based on animal data, ISEMBYLD may affect male and/or female reproductive function.

Please see full Prescribing Information.

Reference: 1. ISEMBYLD. Prescribing Information. Scholar Rock, Inc; 2026.