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

Elahere (mirvetuximab soravtansine-gynx) received full FDA approval on March 22, 2024, for adult patients with folate receptor alpha (FRα) positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer who have received one to three prior systemic treatment regimens. For oncologists and prescribers in 2026, the key challenges are not supply-related — Elahere is not on the FDA Drug Shortage list — but rather structural: companion diagnostic access, insurance prior authorization, and infusion center capability. This article provides a comprehensive overview for clinicians managing PROC patients.

Supply Status: What Prescribers Need to Know

As of 2026, Elahere is not listed on the FDA Drug Shortage Database. AbbVie acquired ImmunoGen in February 2024 and has since significantly expanded the commercial and supply infrastructure for Elahere. The drug is distributed via specialty pharmacy channels to oncology infusion centers and hospital pharmacies.

Elahere is supplied as a sterile, preservative-free injectable solution containing 100 mg/20 mL (5 mg/mL) in single-dose vials. It requires refrigeration and proper cold-chain handling. Standard oncology pharmacy infrastructure at cancer centers is generally adequate for storage and preparation.

Efficacy Reminders: Why Elahere Should Be Prioritized

The Phase 3 MIRASOL trial (NCT04209855) provides the clinical foundation for full approval. In 453 patients with FRα-positive PROC:

Median OS: 16.5 months vs 12.7 months with investigator's choice (IC) chemotherapy (HR 0.67; p=0.0046)

Median PFS: 5.6 months vs 4.0 months (HR 0.65; p<0.0001)

ORR: 42.3% vs 15.9%

The final MIRASOL analysis (30.5-month follow-up, presented at SGO 2025) confirmed a 32% reduction in the risk of death (HR 0.68; p=0.0004) and a median OS of 16.85 months vs 13.34 months.

For FRα-high patients, Elahere is now considered an emerging standard of care in PROC. Timely FRα testing and treatment initiation are critical — discuss these at the time of platinum-resistance determination.

FRα Testing: The Companion Diagnostic Workflow

FRα testing using the VENTANA FOLR1 (FOLR-2.1) RxDx Assay (Ventana Medical Systems) is required before initiating Elahere. Consider these workflow points:

Testing can be performed on archival tumor tissue (FFPE blocks or slides) — a new biopsy is not always required.

Send tissue to a reference lab that runs the VENTANA FOLR1 assay — not all local pathology labs perform this test.

Recommend ordering FRα testing proactively — at time of platinum-resistance determination rather than waiting for a third-line decision, to avoid treatment delays.

About 35% of ovarian cancer patients have high FRα expression (≥75% of cells ≥2+ staining intensity); approximately 80% of high-grade serous OC overexpress FRα at some level.

Prior Authorization: Preparing a Strong Submission

Prior authorization is almost universally required for Elahere given its ~$29,307 per-cycle cost. A well-prepared PA submission should include:

FRα-positive test result from the VENTANA FOLR1 assay (include lab report)

Documentation of platinum-resistant disease (progression within 6 months of platinum therapy)

Prior lines of therapy (1-3) with dates and agents

Reference to FDA full approval (March 22, 2024) and NCCN guideline inclusion

Letter of medical necessity emphasizing OS benefit (MIRASOL: HR 0.67, p=0.0046)

Key Safety Considerations for Prescribers

Elahere carries a boxed warning for ocular toxicity. Mandatory ophthalmic monitoring includes:

Ophthalmic exam (visual acuity + slit lamp) before treatment initiation, every other cycle for the first 8 cycles, and as clinically indicated

Prophylactic artificial tears AND ophthalmic topical steroids starting before the first infusion

Patients should be advised to avoid contact lens use during treatment

Discontinue Elahere for Grade 4 ocular toxicities; withhold and manage for Grade 2-3

Other clinically relevant toxicities include ILD/pneumonitis (monitor for dyspnea, cough, hypoxia; withhold for suspected Grade 2+), peripheral neuropathy, infusion-related reactions, and embryo-fetal toxicity. Premedicate with an antihistamine, corticosteroid, and acetaminophen approximately 30 minutes before each infusion.

Drug Interactions: CYP3A4 Considerations

The cytotoxic payload DM4 is a CYP3A4 substrate. Coadministration with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, clarithromycin, ritonavir, atazanavir) may increase unconjugated DM4 exposure and risk of adverse reactions. Use caution and monitor closely. Avoid coadministration with etrasimod due to additive immunosuppressive effects.

Patient Support Resources for Your Practice

For patients who are struggling to locate an infusion center that administers Elahere, medfinder for providers can help your team quickly identify facilities in a patient's area that can fill the prescription. Additionally, ELAHERE Support Services (1-833-352-4373) provides Case Managers who can navigate insurance and access on the patient's behalf.

See also: How to Help Your Patients Find Elahere in Stock: A Provider's Guide.