Viking Therapeutics Plunges 42% on Weight-Loss Drug Safety Fears

TradingKey - Viking Therapeutics (VKTX.US) shares tumbled over 42% on Tuesday following disappointing mid-stage trial data revealing severe side effects that shattered investor confidence.

The obesity-focused biotech company saw its stock plunge from Monday’s close of $42.09 to Tuesday’s $24.36, hitting an intraday low of $23.21. Viking’s market capitalization shrank from over $4 billion to $2.739 billion.

Source: TradingKey

Trial results showed Viking’s oral weight-loss drug VK2735 achieved 12.2% average weight reduction over 13 weeks — significantly outperforming the placebo group’s 1.3%. However, the drug triggered severe gastrointestinal adverse reactions: 58% of patients experienced nausea, 25% vomiting, and 28% discontinued treatment prematurely.

Analysts widely viewed the high adverse event rate — particularly within the relatively short 13-week trial — as a critical flaw in safety and patient tolerability. "Tolerability concerns overshadowed efficacy data," stated Piper Sandler analyst Biren Amin in a research note.

In contrast, competitors demonstrated stronger profiles. Eli Lilly’s oral weight-loss drug orforglipron achieved 12.4% weight reduction over 72 weeks with discontinuation rates below 20%. Novo Nordisk’s injectable Wegovy showed superior overall performance and has taken the lead in oral drug approval timelines.

Mizuho analyst Jared Holz noted Viking’s data lagged behind Lilly’s across nearly all key metrics, especially the high discontinuation rate. He added this could “probably shutters hope for [Viking] to be a bigtime player in the oral obesity market over the near to medium term.”

Boosted by Viking’s negative news, Novo Nordisk shares rose 1.83% and Eli Lilly saw modest gains on Tuesday.

Source: Google Finance