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(Adds details, comments from FDA reviewers)
By Toni Clarke
May 23 (Reuters) - A preliminary review by the U.S. Food andDrug Administration questioned the usefulness of a combinationdiabetes drug made by Sanofi SA's and said it wasunclear whether one component, lixisenatide, contributed to itsbenefit.
The French drugmaker is seeking approval for lixisenatidealone and as part of a combination product, iGlarLixi, whichSanofi hopes will establish a new paradigm for diabetes therapyby treating patients earlier and more aggressively.
The review comes ahead of a Wednesday meeting of an FDAadvisory panel that will discuss lixisenatide and thecombination treatment, iGlarLixi, an injection which deliverslixisenatide and Sanofi's drug Lantus in a fixed-dosecombination.
The review noted that the lixisenatide component ofiGlarLixi is not the dose established as effective forlixisenatide alone, meaning some patients could be exposed to acomponent that provides no known therapeutic benefit.
On Tuesday, the committee will consider a similarcombination treatment made by Novo Nordisk A/S thatcombines the company's diabetes drugs Victoza and Tresiba. TheFDA's preliminary review of that drug raised similar concerns.
Sanofi was given speedier-than-normal review after it boughta priority review voucher from Retrophin Inc last yearfor $245 million. Retrophin was granted the voucher as part ofan FDA program to spur research into rare pediatric disorders.
Lixisenatide belongs to a class of diabetes treatmentscalled GLP-1 agonists that includes Victoza and Bristol-MyersSquibb Co and AstraZeneca's Byetta and Bydureon.
The panel will be asked whether there are any safety orefficacy issues that preclude approval of lixisenatide, and theywill be asked to vote on whether iGlarLixi should be approved.The FDA is not obliged to follow the recommendation of itsadvisory panels, but typically does so.
Lixisenatide was approved by regulators in Europe and Japanin 2013 and is sold under the brand name Lyxumia. Sanofilicensed the product from Denmark's Zealand Pharma A/S. Novo Nordisk's drug is sold in Europe as Xultophy.
The reviewer, Dr. Jean-Marc Guettier, director of the FDA'sdivision of metabolism and endocrinology products, said they had"reservations" about Sanofi's conclusion that iGlarLixi offeredsuperior blood sugar control than Lantus alone.
"It is unclear whether there is a benefit in the low-doserange that balances the additional safety concerns from adding asecond drug," the division said, adding that trial may havecreated a bias in favor of the combination.
"The treatment difference observed may not reflect theactual treatment difference" they said.
Panelists will be asked to discuss whether use of iGlarLixishould be approved for patients not treated with a basal insulinor a GLP-1, for patients who are inadequately controlled oneither drug, or both.
The goal of both companies' products is to combine a GLP-1and a basal insulin in a single injection instead of two andtreat patients with a combination drug early rather than waitingfor one drug to wane in effect before moving to another.
An FDA decision on lixisenatide is expected in July and oniGlarLixi in August.
Separately, the Sanofi executive in charge of diabetes andcardiovascular products, Pascale Witz, is leaving the company onJune 1 as part of a management shakeup, the company said onMonday. (Reporting by Toni Clarke in Washington, editing by G Crosse)
