Vertex Pharmaceuticals Inc., one of biotechnology’s most richly valued companies, faces a big test Tuesday in proving it can become consistently profitable and live up to its $30 billion market capitalization.

A Food and Drug Administration advisory committee will consider whether to recommend approval of Vertex’s experimental cystic-fibrosis drug, Orkambi, which analysts predict could help the company earn more than $8 billion in net profit over the next four years if it reaches the market.

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