Patritumab deruxtecan HER3 NSCLC breast

Indicated For

NSCLC, breast

About This Medication

# Patritumab Deruxtecan Patient Guide: How to Get This Treatment at Low or No Cost **Important Note:** Patritumab deruxtecan (HER3-DXd, U3-1402) is an investigational drug not yet approved by the FDA for any use. There is no standard commercial patient assistance program available because it is not on the market. Access is limited to special programs like the Medical Access Program (MAP) for eligible patients with serious unmet needs[1][2]. This guide explains current options, focusing on Daiichi Sankyo's general support and MAP details. ## About Patritumab Deruxtecan Patritumab deruxtecan is a **HER3-directed antibody-drug conjugate (ADC)** developed by Daiichi Sankyo in partnership with Merck. It targets HER3-positive cancers by delivering chemotherapy directly to tumor cells, potentially sparing healthy tissue[4][5]. It shows promise in **EGFR-mutated non-small cell lung cancer (NSCLC)** after prior treatments like EGFR tyrosine kinase inhibitors (TKIs) and platinum chemotherapy fail[5][7]. Key trial highlights: - **HERTHENA-Lung01 (Phase 2):** Demonstrated durable tumor responses in advanced EGFR-mutated NSCLC[5][6]. - **HERTHENA-Lung02 (Phase 3):** Met primary endpoint of progression-free survival vs. chemotherapy; overall survival data presented at ASCO 2025[4][7]. A Biologics License Application (BLA) was submitted but voluntarily withdrawn in some regions; FDA priority review was granted earlier with a PDUFA date of June 26, 2024[4][5][7]. As of now, it's unavailable commercially—patients must pursue investigational access[1][2]. ## Who Qualifies for Access? Since there's no standard prescription assistance program, eligibility centers on the **Medical Access Program (MAP)** sponsored by Daiichi Sankyo[1][2]. This is for patients with **life-threatening or serious conditions** where: - Existing treatments don't meet needs. - Patient can't join clinical trials. - Doctor requests expanded access to the investigational drug. MAP is not income-based; it's medically driven for unmet needs in EGFR-mutated NSCLC or similar[1]. Enrollment is ongoing (NCT06099639)[2]. Daiichi Sankyo offers general patient support via **Access Central** for approved drugs like Enhertu and Datroway, which may guide future options[3]. They partner with **Partnership for Prescription Assistance (PPA)** to help find programs[3]. ## Income Eligibility No specific income thresholds apply, as patritumab deruxtecan lacks a commercial PAP. For reference, Daiichi Sankyo's programs for approved drugs often use **400-500% of the Federal Poverty Level (FPL)**, but this is not confirmed for investigational drugs. | Household Size | Estimated Low Income Threshold (e.g., 400% FPL, 2026) | Notes | |---------------|-------------------------------------------------------|-------| | Individual | ~$60,000 | Hypothetical; MAP not income-based[1] | | Couple | ~$81,000 | Consult doctor for MAP | | Family of 3 | ~$102,000 | FPL varies yearly | | Family of 4 | ~$123,000 | No program details available | **Table Note:** These are illustrative based on typical PAPs; patritumab deruxtecan access is via MAP, not financial aid[3]. ## Insurance Requirements MAP is for investigational use outside trials, typically when insurance won't cover unapproved drugs. Commercial insurance, Medicare, or Medicaid may deny investigational treatments. Your doctor submits a compassionate use request to Daiichi Sankyo/Merck. No standard insurance rules apply yet[1][2]. For approved Daiichi drugs, programs often require commercial insurance or Medicare Part D, excluding government insurance[3]. ## Step-by-Step Application Process 1. **Consult Your Oncologist:** Discuss if patritumab deruxtecan fits your EGFR-mutated NSCLC or other HER3+ cancer. Confirm no trial eligibility[1]. 2. **Request MAP Enrollment:** Doctor submits to Daiichi Sankyo via clinicaltrials.gov (NCT06099639) or sponsor contacts. Include medical records showing unmet need[2]. 3. **Provide Documentation:** Proof of diagnosis, prior treatments, trial ineligibility. No income docs needed[1]. 4. **Sponsor Review:** Daiichi Sankyo/Merck evaluates safety/risk. If approved, drug provided free for MAP[1]. 5. **General Support:** Call Daiichi Sankyo Access Central (1-855-438-6658 from their site[3]) or visit pparx.org for guidance[3]. Processing varies; investigational requests can take weeks. ## Timeline and Delivery - **Approval Time:** MAP decisions depend on case; clinical trial-like (days to months)[1]. No fixed processing time. - **Delivery:** Direct to healthcare provider/hospital for administration (IV infusion every 3 weeks, like trials[7]). Free via MAP. - **Treatment Duration:** Until progression or intolerance, per investigator[7]. ## Alternatives if Denied or Ineligible - **Clinical Trials:** Search clinicaltrials.gov for HERTHENA or related (e.g., HERTHENA-Lung02)[4][7]. - **Other ADCs:** Enhertu (approved HER2+), Datroway (EGFR-mutated NSCLC, accelerated approval June 2025[9])[3][9]. - **PPA Resources:** pparx.org matches to 200+ programs[3]. - **Merck PAP:** For approved Merck drugs; inquire for investigational[5]. - **Compassionate Use:** Doctor can request from FDA Expanded Access. No biosimilars exist. ## Disclaimer This guide is for informational purposes only and not medical/financial advice. Patritumab deruxtecan is investigational; efficacy/safety not FDA-established. Consult your doctor. Program details may change; verify with Daiichi Sankyo (accesscentral@dsi.com or 1-855-438-6658[3]). As of 2026, no commercial PAP exists[1][4]. Word count: 952.

Program information last verified: March 30, 2026