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The TGA has completed its investigation of the risk of serious adverse events for specific patient groups in clinical trials associated with idelalisib (Zydelig) 100 mg and 150 mg tablets.
A safety advisory regarding a change to idelalisib's indications and the addition of warnings to its Product Information has been published on the TGA website.
Monitoring communication - risk of serious adverse events for specific patient groups in clinical trials
16 March 2016
Consumers and health professionals are advised that the TGA is investigating a significant safety concern involving idelalisib 100 mg and 150 mg tablets, which are marketed in Australia as Zydelig.
Idelalisib belongs to a group of medicines called antineoplastic agents. It is approved to treat some rare kinds of blood cancer by affecting the growth of cancerous lymphocytes (a type of white blood cell).
The sponsor of idelalisib, Gilead Sciences, has advised the TGA of a potential increased risk of serious adverse events including death, mostly due to infections, in patients receiving the medicine, in combination with other cancer medicines, to treat chronic lymphocytic leukaemia (CLL) and relapsed indolent non-Hodgkin's lymphoma (iNHL) as part of phase 3 clinical trials.
Gilead Sciences has notified the clinical trial investigators who are participating in idelalisib clinical trials involving Australian patients.
The TGA is reviewing information already received and is seeking further data from Gilead Sciences to help determine what actions should be taken in response to this issue. In the meantime, Gilead Sciences is advising prescribers to avoid using idelalisib as a first line treatment. Patients starting or continuing treatment with idelalisib should be carefully monitored for signs of infections. If idelalisib is well tolerated, treatment should not be stopped.
If you or someone you care for is taking idelalisib and you have any questions about your treatment, contact your doctor.
The TGA will provide further appropriate information to consumers and health professionals as it becomes available.
Reporting problems
In addition to adverse events involving idelalisib, consumers and health professionals are encouraged to report all problems with medicines or vaccines. Your report will contribute to the TGA's monitoring of these products.
The TGA cannot give advice about an individual's medical condition. You are strongly encouraged to talk with a health professional if you are concerned about a possible adverse event associated with a medicine or vaccine.