CTI cancer drug faces clouded future after study failure
- A cancer drug approved in Europe to treat a type of lymphoma failed to improve progression-free survival versus a commonly used combination regimen in a late-stage study, potentially putting at risk its position on the market.
- Pixuvri, developed by CTI Biopharma and licensed to French pharma Servier, won a conditional OK in the EU for third- or fourth-line treatment of relapsed B-cell non-Hodgkin lymphoma (NHL) in May 2012. More than six years later, the study designed to confirm those results has turned up negative.
- "We are disappointed with the outcome of the PIX306 trial and will proceed to conduct a thorough review of clinical data to assess the next steps for the Pixuvri program," said CTI CEO Adam Craig in a statement.
Similar to the accelerated approvals granted by the Food and Drug Administration in the U.S., European drug regulators can grant a conditional marketing authorization to promising drugs with limited data.
The idea is that patients can gain earlier access to new medicines for diseases with few treatment options, while clinical work to more fully assess the drug's efficacy remains in progress.
In the decade from 2006 to 2016, the European Medicines Agency has granted conditional approval to 30 medicines, 17 of which were for treatment of various cancers. Over that ten-year span, no conditional marketing authorization was subsequently revoked, although two drugs were withdrawn and 17 remained under a contingent OK at the time of the EMA's report.
Pixuvri (pixantrone)'s case could put that record to the test, after CTI Biopharma and Servier reported the drug failed to meet its goal in a 312-patient, Phase 3 confirmatory study.
PIX306, as the study is known, tested Pixuvri in combination with Rituxan (rituximab) against Rituxan and a commonly used chemotherapy called bendamustine in patients with relapsed NHL and who were not eligible for stem cell transplant.
Detailed results are not available but the statement from the companies indicate the Pixuvri combination did not improve progression-free survival, the study goal, versus the chemo combination. No data were disclosed on whether the Pixuvri regimen showed any benefit on its secondary endpoints, which included overall survival.
The failure could threaten the companies' sought-after label expansion and may put renewal of the drug's conditional approval at risk. Such regulatory OKs are only valid for one year, per European Commission regulations.
Pixuvri isn't a big earner. CTI only earned $600,000 in product sales over the first three months of 2017, before it handed exclusive commercialization rights to Servier last April in exchange for 12 million Euros.
In a recent filing with U.S. regulators, CTI noted that Pixuvri is only available in a limited number of European markets and has secured reimbursement in "even fewer" countries. The success of other drugs, notably AbbVie and Johnson & Johnson's Imbruvica (ibrutinib), has also altered the treatment landscape in some types of NHL.
CTI and Servier had hoped PIX306, if successful, would support a expansion of Pixuvri's label to include second-line treatment of NHL. In that hoped-for outcome, CTI contemplated a potential submission for approval of the drug in the U.S., where CTI still holds commercialization rights.
Those plans are likely now on hold and the drug's position in the EU could be threatened as well. CTI said complete results from PIX306 would be submitted to a "peer-reviewed journal for publication."
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