Tibsovo: Withdrawal of the marketing authorisation application

Tibsovo was developed as a medicine for treating AML that has come back (relapsed) or has not improved with previous treatment (refractory) in adults whose cancer cells have a mutation (change) in the gene for an enzyme called IDH1. It was to be used in:

• patients who have received two previous treatments, including at least one standard intensive treatment with chemotherapy;
• patients who cannot receive standard intensive cancer treatment and have tried at least one non-intensive treatment.

Tibsovo contains the active substance ivosidenib and was to be available as tablets.

Tibsovo was designated an ‘orphan medicine’ (a medicine used in rare diseases) on 12 December 2016 for AML.

The active substance in Tibsovo, ivosidenib, works by blocking the action of mutated forms of IDH1. Mutated IDH1 produces high levels of a substance called D-2-hydroxyglutarate (D-2-HG), which contributes to the growth of cancer cells. By blocking the action of mutated IDH1, ivosidenib is expected to reduce production of D-2-HG and so control the disease.

The company presented results from a main study involving 179 patients with relapsed or refractory AML carrying an IDH1 mutation. The study investigated the effects of different doses of Tibsovo. Tibsovo was not compared with any other medicine and the main measure of effectiveness was the number of patients who no longer showed signs of the disease after treatment, with or without normalisation of blood cell counts.

The application was withdrawn after the European Medicines Agency had evaluated the information from the company and prepared questions for the company. After the Agency had assessed the company’s responses to the last round of questions, there were still some unresolved issues.

Based on the review of the data and the company’s response to the Agency’s questions, at the time of the withdrawal, the Agency had some concerns and its provisional opinion was that Tibsovo could not have been authorised for the treatment of AML.

The Agency concluded that the main study did not provide enough evidence that the medicine is effective in the treatment of AML with an IDH1 mutation.

Therefore, at the time of the withdrawal, the Agency’s opinion was that the company had not provided enough data to support the application for Tibsovo.

In its letter notifying the Agency of the withdrawal of the application, the company stated that it withdrew its application because the Agency considered that the available data were not sufficient to conclude on a positive benefit-risk balance for the proposed indication.

The company informed the Agency that there are no consequences for patients in clinical trials using Tibsovo.

If you are in a clinical trial and need more information about your treatment, speak with your clinical trial doctor.