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Idelalisib oral

Updated 2 Feb 2023 | Idelalisib


Oral formulations of idelalisib.

Drugs List

  • idelalisib 100mg tablets
  • idelalisib 150mg tablets
  • ZYDELIG 100mg tablets
  • ZYDELIG 150mg tablets
  • Therapeutic Indications


    Chronic lymphocytic leukaemia with anti-CD20 monoclonal antibody
    Maintenance for patients with relapsed / refractory follicular lymphoma

    Monotherapy for follicular lymphoma (FL), refractory to two previous treatments.

    Treatment of adult chronic lymphocytic leukaemia (CLL), in combination with anti-CD20 monoclonal antibody (rituximab or ofatumumab):
    In patients who have received one prior treatment.
    As first line treatment in patients with 17p deletion or TP53 mutation who were unsuitable for other therapies.


    Whilst the doses stated below are those recommended by the manufacturer, local cancer network protocols for the relevant indication should be consulted.


    150mg twice daily.
    Treatment should continue until disease progression or unacceptable toxicity.

    Additional Dosage Information

    Grade 3 or 4 aminotransferase elevation (ALT or AST greater than 5 x upper limit of normal (ULN))
    Suspend treatment until grade 1 values (ALT or AST less than or equal to 3 ULN) have been reached, resume treatment at 100mg twice daily.
    Monitor for symptoms and increase to 150mg twice daily, depending on patient tolerance.
    If symptoms reoccur suspend treatment until values return to grade 1 and resume treatment at 100mg twice daily if suitable.

    Grade 3 or 4: Diarrhoea/colitis or rash
    Suspend treatment until symptoms have returned to grade 1, resume treatment at 100mg twice daily.
    Monitor for symptoms and increase to 150mg twice daily, depending on patient tolerance.

    Suspend treatment until symptoms resolve, if appropriate resume treatment at 100mg twice daily.
    Discontinue permanently in cases of moderate or severe symptomatic pneumonitis or organising pneumonia.

    Absolute neutrophil count (ANC) less than 500per cubic mm
    Suspend treatment until ANC is above 500per cubic mm, monitor ANC at least weekly until ANC is greater than or equal to 500per cubic mm
    Then resume treatment at 100mg twice daily.

    Absolute neutrophil count (ANC) greater than 500per cubic mm
    Maintain regular treatment.
    Monitor ANC at least weekly until ANC is greater than or equal to 1000per cubic mm.

    Missed dose
    If the patient misses a dose within 6 hours of the time it is usually taken, the patient should take the missed dose as soon as possible and resume normal dosing schedule.
    If the patient misses a dose by more than 6 hours, the missed dose should not be taken. The patient should then resume the usual dosing schedule.


    Children under 18 years

    Precautions and Warnings

    Females of childbearing potential
    Hepatic impairment

    Prophylaxis for pneumocystis jiroveci pneumonia recommended
    Treatment to be initiated and supervised by a specialist
    Some formulations contain sunset yellow (E110); may cause allergic reaction
    Consult local policy on the safe use of oral anti-cancer drugs
    Staff: Not to be handled by pregnant staff
    Consider immunosuppressant adjustment in the event of PML
    Monitor AST, ALT and total bilirubin every 2 weeks for first 3 months
    Monitor neutrophil count every 2 weeks for first 6 months of treatment
    Monitor neutrophil count weekly if ANC is less than 1000 per cubic mm
    Monitor patients with hepatic impairment for adverse effects
    Monitor regularly for cytomegalovirus (CMV) infection
    Monitor respiratory function
    Advise patient to report any new or worsening respiratory symptoms
    Advise patient to report headaches, seizures, confusion, visual disturbance
    Advise patient to report symptoms of infection immediately
    Discontinue if active infection develops
    Discontinue if cryptogenic organising pneumonia occurs
    Discontinue if moderate or severe pneumonitis occurs
    Discontinue treatment if DRESS is confirmed
    Discontinue treatment if Stevens-Johnson syndrome is confirmed
    Discontinue treatment if toxic epidermal necrolysis is confirmed
    Reduce dose if grade 3 or 4 toxicities occur
    Suspend treatment if DRESS is suspected
    Suspend treatment if grade 3 or worse diarrhoea or colitis occurs
    Suspend treatment if grade 3 or worse skin reaction occurs
    Suspend treatment if pneumonitis is suspected
    Suspend treatment if Stevens-Johnson syndrome is suspected
    Suspend treatment if toxic epidermal necrolysis is suspected
    Discontinue if Progressive multifocal leukoencephalopathy (PML) develops
    Interrupt treatment if ALT or AST > 5 x ULN
    Suspend treatment if neutrophil count < 500 cells per cubic mm
    Advise patient not to take St John's wort concurrently
    May cause impaired fertility
    Female: Barrier or non-hormonal contraception required during treatment
    Female: Contraception required during and for 1 month after treatment
    Advise patients to report skin rash

    If grade 2 or more elevations in ALT or AST are observed, monitor patients weekly until values have returned to grade 1 or less.

    All patients should receive prophylaxis for Pneumocystis jirovecii pneumonia (PJP) during treatment and for 2 to 6 months following the end of treatment. Length of continued prophylaxis should be based on risk factors for opportunistic infections such as such as corticosteroid treatment and prolonged neutropenia.

    Progressive multifocal leukoencephalopathy syndrome (PML) has been reported in some patients treated with this agent. If patients present with symptoms indicating PML such as worsening neurological, cognitive or behavioural signs or symptoms, an MRI should be performed. If PML is diagnosed, treatment should permanently discontinued.

    Pregnancy and Lactation


    Idelalisib is contraindicated during pregnancy.

    Use of idelalisib during pregnancy is contraindicated by the manufacturer. Animal studies have shown teratogenic effects. Human data is limited and as a potential risk cannot be ruled out.


    Idelalisib is contraindicated during breastfeeding.

    Use if idelalisib when breastfeeding is contraindicated by the manufacturer. It is not known if idelalisib and its metabolites are excreted in human milk. Effects on exposed infants are unknown.

    Side Effects

    Cryptogenic organising pneumonia
    Cytomegalovirus infection
    Drug rash with eosinophilia and systemic symptoms (DRESS)
    Elevated triglyceride levels
    Erythematous rash
    Exfoliative dermatitis
    Hepatic failure
    Hepatocellular damage
    Increase of liver transaminases
    Increases in hepatic enzymes
    Maculopapular rash
    Pneumocystis jiroveci pneumonia
    Progressive multifocal leukoencephalopathy (PML)
    Pruritic rash
    Skin disorder
    Stevens-Johnson syndrome
    Toxic epidermal necrolysis


    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: May 2019

    Reference Sources

    NICE Evidence Services Available at: Last accessed: 28 May 2019

    Summary of Product Characteristics: Zydelig 100mg film-coated tablets. Gilead Sciences Ltd. Revised January 2021.
    Summary of Product Characteristics: Zydelig 150mg film-coated tablets. Gilead Sciences Ltd. Revised January 2021.

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