Temozolomide Shortage: What Providers and Prescribers Need to Know in 2026

For neuro-oncologists, medical oncologists, and other prescribers managing patients on temozolomide (Temodar), understanding the current supply landscape is essential to preventing treatment interruptions. While temozolomide is not currently on the FDA's active drug shortage list as of 2026, specialty pharmacy access barriers, multi-strength prescribing complexity, and insurance prior authorization requirements create real risks of treatment cycle delays for your patients.

Current Supply Status: Not in Official Shortage, But Localized Gaps Persist

Temozolomide has multiple generic manufacturers as of 2026, including Lannett, Amneal, Sun Pharma, and Camber Pharmaceuticals (which launched a new generic in May 2025). Brand-name Temodar continues to be produced by Merck. This diversity of supply reduces the risk of a national shortage. However, prescribers should be aware of the following structural access barriers that affect patients regardless of national supply levels:

• Retail pharmacy stocking: Most retail community pharmacies do not routinely stock temozolomide due to low demand volume and its specialty drug classification. Patients sent to retail pharmacies frequently encounter "not in stock" responses.
• Multi-strength complexity: Temozolomide is available in 5 mg, 20 mg, 100 mg, 140 mg, 180 mg, and 250 mg capsules, and BSA-based dosing frequently requires multiple strengths per prescription. A pharmacy may carry 100 mg but not 5 mg or 20 mg capsules — blocking the patient from completing their cycle dose.
• Prior authorization timelines: Nearly every commercial insurer and Medicare Part D plan requires prior authorization for temozolomide, a specialty tier medication. PA processing typically takes 2–7 business days, compressing the window between cycle completion and the next cycle start.

Updated FDA Labeling: What Changed in September 2023

In September 2023, the FDA approved updated labeling for temozolomide under Project Renewal, an Oncology Center of Excellence initiative aimed at keeping older oncology drug labels current. Key updates included:

• A new indication: adjuvant treatment of adults with newly diagnosed anaplastic astrocytoma
• Revised and updated dosing regimens for newly diagnosed GBM and refractory anaplastic astrocytoma
• Addition of explicit capsule exposure risk language under Warnings and Precautions — capsules must not be opened, chewed, or dissolved

Key Safety Reminders for Prescribers

When prescribing or renewing temozolomide, remind your team of the following clinical considerations:

• CBC monitoring: Obtain CBC weekly during the concomitant RT phase; on Day 1 and Day 22 of each maintenance cycle; and weekly until recovery if ANC falls below 1.5 × 10⁹/L or platelets below 100 × 10⁹/L.
• PCP prophylaxis: Required for all patients during the concomitant RT phase (42-day regimen). Continue in patients who develop lymphopenia until resolution to Grade ≤1.
• Hepatotoxicity monitoring: Obtain LFTs at baseline and periodically. Advise patients to report symptoms of hepatotoxicity.
• Secondary malignancies: Cases of myelodysplastic syndrome and secondary acute myeloid leukemia have been observed following temozolomide-containing regimens. Advise patients of this risk.
• Reproductive toxicity: Contraception required during treatment and for 6 months post-treatment for females and 3 months for males. Confirm pregnancy status before starting.

How to Minimize Access Delays for Your Patients

Proactive prescription management reduces the risk of treatment gaps:

1. Route prescriptions to verified specialty pharmacies (CVS Specialty, Accredo, BriovaRx, or your cancer center's dispensary) rather than leaving patients to find a retail pharmacy.
2. Submit prior authorization requests at least 7–10 days before the next cycle start date. Use the cycle schedule to plan PA renewal timelines proactively.
3. Prescribe all required capsule strengths explicitly on one prescription to prevent pharmacies from dispensing only partial doses.
4. Assign a nurse navigator or pharmacy liaison to follow up on fill status for patients in active treatment cycles.
5. Recommend medfinder for providers as a resource for patients who need to locate their specific temozolomide strength at pharmacies near them.

The Broader Oncology Drug Shortage Context

The 2024 report from ASHP and GAO underscored that oncology and sterile injectable drugs remain the most vulnerable categories in the U.S. drug supply chain. While temozolomide's current supply is stable, prescribers should maintain contingency protocols. If you manage patients who cannot get temozolomide, lomustine (Gleostine/CCNU) and bevacizumab (Avastin, FDA-approved for recurrent GBM) are the most commonly considered alternatives — always on a case-by-case basis with individualized clinical judgment.

For a practical guide on how to help your patients find temozolomide, see: How to Help Your Patients Find Temozolomide in Stock: A Provider's Guide.