CAMBRIDGE, Massachusetts (

TheStreet

) --

Genzyme

(GENZ)

is exploring a new deal structure that could break an acquisition deadlock with

Sanofi-Aventis

(SNY) - Get Report

, the

Wall Street Journal

reports.

Genzyme is considering a structure known as a contingent value right, which gives shareholders an added benefit once an acquired company hits a future benchmark, the

Journal

reports.

The CVR would be largely tied to the performance of Campath, a Genzyme drug used to treat leukemia but that is being tested for use on multiple sclerosis, people familiar with the matter told the newspaper.

Genzyme has been holding internal discussions about how to structure such a deal with Sanofi, the

Journal

reports.

Sanofi has said Genzyme is too optimistic in its projection for Campath's use on multiple sclerosis.

Genzyme has been trying to fend off an $18.5 billion hostile bid from France's Sanofi.

-- Written by Joseph Woelfel

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Joseph Woelfel

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