Swissmedic Approves Two Orphan Drugs for Rare Cancers: Ayvakyt for GIST and Mastocytosis, VANFLYTA for FLT3-ITD AML
Key Insights
Swissmedic (search) has authorized Ayvakyt (avapritinib) for treating adults with PDGFRA-D842V (search) mutated gastrointestinal stromal tumors and advanced systemic mastocytosis (search) following prior systemic therapy.
VANFLYTA (quizartinib) received approval for newly diagnosed acute myeloid leukemia (search) patients with FLT3-ITD (search) mutations, administered through induction, consolidation, and maintenance therapy phases.
Both medications were designated as orphan drugs for rare, life-threatening diseases and approved under Article 13 based on FDA and EMA assessments.
Swissmedic (search) has authorized two new orphan drugs for treating rare and aggressive cancers, providing critical therapeutic options for patients with limited treatment alternatives. Both Ayvakyt (avapritinib) and VANFLYTA (quizartinib) received approval under Article 13 of the Therapeutic Products Act, allowing Swiss patients access to medicines already authorized by comparable international regulatory agencies.
Ayvakyt Targets Rare GIST and Mastocytosis
Ayvakyt, containing the active substance avapritinib, addresses two distinct rare cancer populations. The drug is indicated for adults with gastrointestinal stromal tumors (GIST (search)) harboring the specific PDGFRA-D842V (search) gene mutation that are either inoperable or have metastasized to other body parts.
The medication also treats advanced systemic mastocytosis (search) (AdvSM (search)) in patients who have received at least one prior systemic therapy. This indication encompasses aggressive systemic mastocytosis (search), systemic mastocytosis associated with hematological neoplasms, and mast cell leukemia (search).
For GIST (search) treatment, the recommended dose is 300 mg once daily, while AdvSM (search) patients receive 200 mg once daily. The film-coated tablets must be taken on an empty stomach, at least two hours before or one hour after meals. Treatment should not be initiated for AdvSM patients with platelet counts below 50 x 10⁹/L.
Safety Profile and Adverse Events
In GIST (search) patients, the most common adverse reactions included anemia (54%), nausea (48%), fatigue (45%), diarrhea (33%), and periorbital edema (32%). Additional frequent side effects were vomiting (28%), facial edema (28%), elevated bilirubin levels (28%), decreased appetite (27%), and peripheral edema (26%).
For AdvSM (search) treatment, peripheral edema occurred in 43% of patients, while anemia, periorbital edema, and thrombocytopenia each affected 40% of patients. Diarrhea was reported in 28% and nausea in 24% of AdvSM patients.
VANFLYTA Addresses Aggressive AML Subtype
VANFLYTA represents a targeted approach for newly diagnosed acute myeloid leukemia (search) patients with FLT3-ITD (search) mutations, a genetic modification associated with rapidly progressing disease that can be fatal within short timeframes without treatment. AML (search) ranks among the most common leukemia forms in adults.
The treatment protocol involves multiple phases, beginning with VANFLYTA combined with standard chemotherapy consisting of cytarabine and anthracyclines during induction therapy. This is followed by consolidation therapy with additional cytarabine chemotherapy, then maintenance therapy with VANFLYTA alone. The drug is not indicated for maintenance following allogeneic hematopoietic stem cell transplantation.
Patients must undergo genetic testing to confirm FLT3-ITD (search) mutation status before initiating treatment, ensuring the targeted therapy reaches appropriate candidates.
Cardiac and Infection Risks
VANFLYTA carries significant safety considerations, including QT interval prolongation that may cause severe cardiac arrhythmias and potential cardiac arrest. Regular electrocardiograms and monitoring of blood potassium and magnesium levels are required throughout treatment.
The medication increases infection risk, particularly in older patients during initial treatment phases. Close monitoring for severe infections during induction therapy is essential.
Common adverse effects affecting more than 10% of patients include infections, lymphocytopenia, leukopenia, anemia, thrombocytopenia, hypokalemia, bleeding, neutropenia, nausea, fever, diarrhea, hypomagnesemia, abnormal liver function tests, vomiting, abdominal pain, stomatitis, edema, headaches, fatigue, rash, pneumonia, upper respiratory tract infections, reduced appetite, sepsis, and various fungal and viral infections.
Regulatory Pathway and Access
Both medications received orphan drug designation due to their treatment of rare, life-threatening conditions. Swissmedic (search)'s approval under Article 13 considered assessments from the FDA for Ayvakyt and both the European Medicines Agency (search) and FDA for VANFLYTA, conducting only limited additional scientific review.
This regulatory approach aims to expedite patient access to medicines already authorized in countries with comparable drug control systems, ensuring Swiss patients can benefit from innovative therapies without unnecessary delays while maintaining safety and efficacy standards.