Krystal Biotech Inc. (KRYS) shares tumbled 9.29% during intraday trading on Monday, deepening a slide that began in the pre-market session after the company released its second-quarter financial results and full-year spending forecast.

The sharp decline was triggered by a revenue shortfall for its flagship gene therapy, VYJUVEK. Global net sales reached $119.2 million, falling short of the $122 million consensus estimate, and the 24% year-over-year growth disappointed against expectations of 32.72%. With Q1 revenue at $116.4 million, sequential growth was minimal, raising concerns about the product’s commercial ramp. Despite an earnings beat—EPS of $1.79 versus the $1.62 estimate—and a 43% rise in net income, the top-line miss dominated sentiment.

Adding to the selling pressure, the company guided for fiscal 2026 non-GAAP R&D and SG&A expenses of $175 million to $195 million, signaling a higher cost structure that could weigh on future profitability. The stock had also rallied in recent weeks following its inclusion in the S&P MidCap 400 index, prompting profit-taking as the revenue miss and expense outlook punctured the bullish narrative.