Drug interactions
Apalutamide + Fostemsavir
Severity: Contraindicated
Apalutamide and Fostemsavir: contraindicated interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Strong CYP3A4 inducers substantially reduce exposure to temsavir, the active form of fostemsavir. Subtherapeutic levels risk virologic failure and resistance development in patients with multidrug-resistant HIV.
What this interaction means in plain words
Apalutamide and Fostemsavir are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two.
Apalutamide belongs to Endocrine; Fostemsavir belongs to Anti Virals.
Why it happens
Apalutamide induces CYP3A4, accelerating the clearance of temsavir.
What to do
Avoid the combination; use a different antiandrogen therapy if fostemsavir is needed. Monitor HIV RNA if exposure to the inducer was recent.
What to ask your pharmacist
- Is there an alternative to one of these two medicines for me?
- If both are essential, who is monitoring me and how often?
- Which symptoms mean I should stop and seek help straight away?
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Other interactions of Apalutamide
- Apalutamide + Cabotegravir Contraindicated
- Apalutamide + Cobicistat Contraindicated
- Apalutamide + Doravirine Contraindicated
- Apalutamide + Elbasvir / grazoprevir Contraindicated
- Apalutamide + Ensitrelvir Contraindicated
- Apalutamide + Isavuconazonium Contraindicated
Other interactions of Fostemsavir
- Carbamazepine + Fostemsavir Contraindicated
- Enzalutamide + Fostemsavir Contraindicated
- Fostemsavir + Mitotane Contraindicated
- Fostemsavir + Phenytoin Contraindicated
- Fostemsavir + Rifampicin Contraindicated
- Efavirenz + Fostemsavir Major
Frequently asked questions
Can I take Apalutamide with Fostemsavir?
MediHelp rates the interaction as contraindicated. Apalutamide and Fostemsavir are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two. Strong CYP3A4 inducers substantially reduce exposure to temsavir, the active form of fostemsavir. Subtherapeutic levels risk virologic failure and resistance development in patients with multidrug-resistant HIV.
How serious is the interaction between Apalutamide and Fostemsavir?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination; use a different antiandrogen therapy if fostemsavir is needed. Monitor HIV RNA if exposure to the inducer was recent.
What other medicines interact with Apalutamide?
MediHelp also lists interactions of Apalutamide with, for example, Cabotegravir, Cobicistat, Doravirine. The full list is on the Apalutamide page.
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