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Fostemsavir oral

Updated 2 Feb 2023 | Other antiretrovirals


Oral formulation of fostemsavir.

Drugs List

  • fostemsavir 600mg modified release tablet
  • RUKOBIA 600mg modified release tablet
  • Therapeutic Indications


    HIV infection in adults- in combination with other antiretrovirals

    Fostemsavir, in combination with other antiretrovirals, is indicated for the treatment of adults with multidrug resistant HIV-1 infection for whom it is otherwise not possible to construct a suppressive anti-viral regimen.


    Fostemsavir should be prescribed by physicians experienced in the management of HIV infection.


    600mg twice daily.

    Additional Dosage Information

    Missed doses
    If a patient misses a dose of fostemsavir, the patient should take the missed dose as soon as the patient remembers, unless it is almost time for the next dose. In this case, the missed dose should be skipped and the next dose should be taken according to the dosing schedule. The patient should not take a double dose.


    Children under 18 years
    Long QT syndrome
    Torsade de pointes

    Precautions and Warnings

    Family history of long QT syndrome
    Electrolyte imbalance
    Hepatitis B
    Hepatitis C
    History of torsade de pointes

    Correct electrolyte disorders before treatment
    Treatment does not prevent risk of transmission of HIV
    Advise ability to drive/operate machinery may be affected by side effects
    Treatment should be initiated by doctor experienced in HIV management
    Autoimmune disorders can occur many months after initiation of treatment
    Consider monitoring ECG in patients at risk of QT prolongation
    Monitor ECG in patients at risk of QT prolongation
    Monitor serum electrolytes
    Advise patient to seek medical advice if joint aches or pain occur
    Inflammatory symptoms should be evaluated and treated appropriately
    May develop immune reactivation syndrome
    Risk of developing opportunistic infections
    Advise patient not to take St John's wort concurrently

    Typically, immune reactivation syndrome reactions have been observed within the first few weeks or months of initiation of the antiretroviral treatment. For example, cytomegalovirus retinitis, generalised and/or focal mycobacterial infections, and Pneumocystis jirovecii pneumonia. Autoimmune disorders (such as Graves' disease, autoimmune hepatitis, polymyositis and Guillain-Barre syndrome) have also been observed, however, the reported time to onset is more variable and these reactions can occur many months after initiation of treatment.

    In patients with hepatitis B and/or C co-infection, monitoring of liver chemistries are recommended. Patients with chronic hepatitis B or C treated with combination antiretroviral therapy are at an increased risk of severe and potentially fatal hepatic adverse reactions. In the case of concomitant antiviral therapy for hepatitis B or C, please refer also to the relevant product information for these medicinal products.

    Pregnancy and Lactation


    Fostemsavir is contraindicated during pregnancy.

    The manufacturer recommends that it is preferable to avoid the use of fostemsavir during pregnancy. At the time of writing there is limited data regarding the use of fostemsavir during pregnancy. Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity, however, fostemsavir and/or its metabolites have been known to cross the placenta in some species. Human data is limited and as such a potential risk cannot be ruled out.


    Fostemsavir is contraindicated during breastfeeding.

    The manufacturer recommends that HIV infected women do not breastfeed their infants under any circumstances in order to avoid transmission of HIV. It is unknown whether fostemsavir/temsavir are excreted in human milk. Animal data have shown excretion of fostemsavir into breast milk however presence in human breast milk is unknown. Effects on exposed infants are unknown.

    Side Effects

    Abdominal pain
    Autoimmune disorders
    Autoimmune hepatitis
    Creatine phosphokinase increased
    Graves' disease
    Guillain-Barre syndrome
    Immune Reactivation/Reconstitution Syndrome
    Increase in serum transaminases
    Opportunistic infections
    Prolongation of QT interval
    Serum creatinine increased


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: December 2021

    Reference Sources

    Summary of Product Characteristics: Rukobia 600mg prolonged-release tablets. ViiV Healthcare UK Limited. Revised September 2021.

    NICE Evidence Services Available at: Last accessed: 21 December 2021

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    FDB Disclaimer : FDB Multilex is intended for the use of healthcare professionals and is provided on the basis that the healthcare professionals will retain FULL and SOLE responsibility for deciding what treatment to prescribe or dispense for any particular patient or circumstance.