Why Vertex Pharma Popped, As A Key Rival Plummeted 90%

Vertex stock surged Monday after its competitor, Sionna Therapeutics (SION), missed the mark for its highly anticipated cystic fibrosis treatment. Sionna's drug, SION-719, lowered sweat chloride by 1 millimole per liter, on average and compared to a placebo, when added to Vertex Pharmaceuticals' (VRTX) Trikafta. Measuring chloride, or salt, in sweat is the gold standard for diagnosing cystic fibrosis, a…