Despite the seemingly positive data, Viking’s shares fell about 11% Tuesday. The investor reaction may be due to disappointment that a deal with, or sale of, the biotech – which may be necessary to propel its pipeline to pivotal testing – has yet to materialise.
Regardless of the stock move, the Phase IIb data suggest that Viking’s VK2809 offered greater improvements on a pair of key histological measurements than fellow THR-β selective agonist Rezdiffra, with a similar safety profile. Viking revealed last year that VK2809 had hit its primary endpoint in the VOYAGE study by significantly lowering liver fat content relative to placebo. The updated data detail results on the same two histological measurements – resolution of MASH with no worsening of fibrosis, and at least a one-stage reduction in fibrosis with no worsening MASH – that supported Rezdiffra’s FDA approval. In VOYAGE, of 44 patients who received 10mg of VK2809 every other day, 75% experienced a resolution of MASH with no worsening of fibrosis, compared with a rate of 29.3% for the placebo arm, for an overall placebo-adjusted improvement of 45.7%. The same treatment arm had 56.8% of patients experience a fibrosis improvement of one stage or more with no worsening of MASH, versus 34.1% for placebo, equalling a placebo-adjusted improvement of 22.7%. According to analysts from Jefferies, 100mg daily Rezdiffra had about a 20% placebo-adjusted improvement in MASH resolution with no worsening of fibrosis, and a roughly 12% placebo-adjusted fibrosis improvement in fibrosis of one stage or more with no worsening of MASH. In terms of safety, in Rezdiffra’s pivotal study, most of the reported side effects were mild-to-moderate, with a roughly 11-13% serious adverse event (AE) rate.
Viking’s study similarly saw that the majority of treatment-related AEs were mild or moderate. About 6.1% of patients who received VK2809 discontinued treatment due to an AE, compared with 9.2% of those in the placebo arm. Viking’s MASH candidate is no longer its most attention-grabbing candidate, with the Jefferies analysts even acknowledging that investors are paying it “limited attention” due to VK2809’s slow development, plus it has an unclear and limited intellectual property portfolio in a “competitive and out-of-favour MASH market.” The jewel in investors’ eye is now Viking’s subcutaneous and oral formulations of its dual GLP-1/GIP receptor agonist VK2735GLP-1/GIP receptor agonist VK2735. In February, the biotech reported that the injectable version achieved placebo-adjusted mean weight loss of up to 13.1% after 13 weeks in a mid-stage study, and in March, the pill formulation led to a placebo-adjusted mean weight loss of up to 3.3% after 28 days. For more, see Spotlight On: Superior safety could be key for Viking’s oral obesity drug, says CEO. When the Phase II VENTURE data were released, Viking was thought to be a likely take-out target due to the best-in-class weight-loss potential of VK2735 and its safety profile, as there were no cases of severe nausea in the study. For more, see Vital Signs: Is Viking sailing to an acquisition? In an earlier note previewing the VOYAGE data, the Jefferies analyst noted that a MASH approval would need another study, which in turn would likely require some sort of partnership.