Limited Distribution Drugs 101

Summary

• Limited distribution drugs (LDDs) are specialty medications available only through select pharmacies, typically used for rare or complex conditions like cancer, cystic fibrosis, and multiple sclerosis.
• Manufacturers restrict LDD distribution due to special handling requirements, safety concerns, and a desire for greater control over patient treatment, sometimes involving FDA safety programs or value-based arrangements.
• Reimbursement for LDDs is more complex than for standard drugs, often requiring detailed prior authorization and specialized pharmacy staff; manufacturers may offer financial assistance to help patients manage high costs.

What are limited distribution drugs (LDDs)? 

Limited distribution drugs (LDDs) are specialty medicines that are only available in certain specialty pharmacies. LDDs often treat rare or complex medical conditions and are expensive. Examples of conditions that often require LDDs are cancer, cystic fibrosis, multiple sclerosis, and hemophilia. In addition, many times they have special requirements related to handling, monitoring, and administering.

Recently approved LDDs

Examples of some recently approved LDDs are:

1. Myqorzo™ (aficamten) approved in December 2025 to treat adults with symptomatic hypertrophic cardiomyopathy.
2. Brinsupri ™ (brensocatib) approved in August 2025 to treat non-cystic fibrosis bronchiectasis in adults and children age 12 and older.
3. Yeztugo® (lenacapavir) approved in June 2025 as pre-exposure prophylaxis (PrEP) to reduce the risk of acquired HIV in adults and adolescents weighing at least 35kg.

Manufacturers restrict distribution of these drugs for several reasons. LDDs often have special requirements (for example, related to storage), and manufacturers may not want to pay for costs necessary to get credentials for a large pharmacy network in order to meet these requirements. Some LDDs may have certain safety issues and be subject to the FDA’s Risk Evaluation and Mitigation Strategies (REMS) program.  REMS is a drug safety program for some medications with major safety concerns to make sure their benefits outweigh risks. Additionally, some manufacturers may want more control over patients’ treatment and so LDDs may be part of a value-based arrangement between a manufacturer and a pharmacy benefits manager.

What is the reimbursement model for LDDs? 

Reimbursement for LDDs is different from other types of drugs. It is usually more complex in part because of their expense and specialized nature. Prior authorization (PA) is often required for LDDs, and the process is more involved than for other kinds of medications. Trained specialty pharmacy staff usually handle much of the PA process, helping to submit paperwork and track status.

LDDs could fall under the medical or pharmacy benefit depending on what type of drugs they are and where they are administered. That can affect out-of-pocket costs for patients. Manufacturers frequently offer patient assistance programs or copay support because the medicines are so expensive.

What is a high-touch care model?

LDDs have a high-touch care model with a clear focus on patients. There are care teams that provide personalized onboarding and education along with clinical monitoring and compliance tracking.

Care teams ensure that patients know how to take their medications and understand side effects. They can even coordinate with prescribers and other healthcare professionals. They also track effectiveness of medicines and counsel patients, serving as a connection among patients, pharmacy, and provider. This results in a more personalized and high-touch experience, which is designed to better serve patients and improve outcomes.

LDDs in general are more complex than standard medicines. They are usually on the expensive side, require PA, and have complicated reimbursement requirements. In addition, LDDs necessitate a high-touch approach from a specialty pharmacy care team. Patients must understand how to take their medicines and care teams track effectiveness and compliance.

References

What is a limited distribution drug (LDD)? Drugs.com. September 13, 2024.

Cytokinetics Announces FDA Approval of MYQORZO™ (aficamten) for the Treatment of Adults with Symptomatic Obstructive Hypertrophic Cardiomyopathy to Improve Functional Capacity and Symptoms. Cytokinetics. December 19, 2025.

FDA Approves BRINSUPRI™ (brensocatib) as the First and Only Treatment for Non-Cystic Fibrosis Bronchiectasis, a Serious, Chronic Lung Disease. Insmed. August 12, 2025.

Yeztugo® (Lenacapavir) Is Now the First and Only FDA-Approved HIV Prevention Option Offering 6 Months of Protection. Gilead. June 18, 2025.

Fein, Adam J. Smaller Pharmacies, Bigger Impact: Inside Manufacturers’ Specialty Networks in 2025. Drug Channels. April 23, 2025.

Dresser, Jesse C. and Girgis, Timothy. Understanding Limited Distribution Drugs Networks: How Pharmacies Are Selected and Strategies to Expand Access. Frier Levitt. December 11, 2025.

Risk Evaluation and Mitigation Strategies | REMS. Food & Drug Administration. May 20, 2025.