Is Lytobi Approved for Bile Duct Cancer?
No, Lytobi (selpercatinib) is not approved for bile duct cancer (cholangiocarcinoma). The FDA approved it in September 2022 for adults with locally advanced or metastatic solid tumors harboring a progressive disease-specific NTRK gene fusion, but this approval excludes primary brain tumors and applies only after prior therapies.[1] Bile duct cancer does not receive specific mention in its labeling.
What Cancers Is Lytobi Approved For?
Lytobi targets RET fusion-positive cancers:
- Non-small cell lung cancer (NSCLC) with RET fusion (approved 2020).
- Thyroid cancers (medullary and RET fusion-positive thyroid) (approved 2020, expanded 2022).
- The 2022 tumor-agnostic approval covers any RET fusion-positive solid tumor after prior systemic therapy.[1][2]
It is marketed by Eli Lilly and Loxo Oncology.
Does Lytobi Work Against Bile Duct Cancer?
Limited evidence exists. RET fusions occur in 1-2% of cholangiocarcinomas, potentially qualifying patients for off-label use under the tumor-agnostic approval if they have progressed on prior treatments.[3] Phase 1/2 LIBRETTO-001 trial data showed responses in RET fusion-positive biliary tract cancers (subset of cholangiocarcinoma), with 43% objective response rate in 7 patients, but numbers are small.[4] No dedicated phase 3 trials target bile duct cancer.
Ongoing Trials for Lytobi in Bile Duct Cancer?
LIBRETTO-431 (phase 3) compares selpercatinib to chemotherapy in RET fusion-positive advanced solid tumors, including biliary tract cancers (NCT04194944). Early data from LIBRETTO-001 supported responses in rare subsets like cholangiocarcinoma.[4] Check ClinicalTrials.gov for enrollment.
Alternatives for Bile Duct Cancer with RET Fusions?
Pralsetinib (Gavreto) shares the tumor-agnostic RET fusion approval and showed activity in biliary cancers.[5] Standard treatments include gemcitabine-cisplatin, durvalumab (immunotherapy), or pemigatinib/ivosidenib for FGFR2/IDH1 mutations (more common in bile duct cancer, ~10-15%).[6]
When Does Lytobi's Patent Expire?
Key U.S. patents for selpercatinib expire in 2031-2033, with pediatric exclusivity potentially extending to 2034. No challenges listed yet on DrugPatentWatch.com.7
[1]: FDA.gov - Lytobi approval (Sep 2022)
[2]: FDA.gov - Initial RET approvals (2020)
[3]: JCO Precision Oncology - RET in cholangiocarcinoma (2021)
[4]: NEJM - LIBRETTO-001 trial (2020)
[5]: Lancet Oncology - Pralsetinib in RET tumors (2021)
[6]: NCCN Guidelines - Biliary Tract Cancers (v2.2023)