Novavax (NVAX) will supply its Matrix-M adjuvant for use in Sanofi's (SNY) pandemic influenza vaccine candidate program, expanding their collaboration and licensing deal.

Sanofi recently received funding from a branch of the US Department of Health and Human Services for early-stage work on the vaccine candidate, which includes the Matrix-M, an adjuvant designed to enhance the immune response, Novavax said Tuesday in a statement.

The amended deal enables use of Matrix-M in through Phase 2 development. If Sanofi advances to Phase 3 clinical trials, the companies will negotiate license rates and financial terms, Novavax said. The original collaboration had outlined a milestone structure.

Novavax shares fell 1.4% in recent Tuesday trading, and Sanofi rose 0.5%.

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