Shares of Allakos Inc. jumped more than 100% as the company reported that its digestive disorder treatment AK002 reduced inflammation in a mid-stage study, meeting its primary goal.
Redwood, Calif.-based Allakos' stock jumped 116.90% to $67.24, a $36.24 increase as of 12:07 p.m. ET on Aug. 5.
AK002 was evaluated in a four-month phase 2 study that included 65 patients with eosinophilic gastritis or eosinophilic gastroenteritis, also known as EG and EGE, respectively. EG and EGE are eosinophilic gastrointestinal diseases, severe inflammatory conditions of the stomach or small intestine. No U.S. Food and Drug Administration-approved treatments exist for these conditions, which can cause abdominal pain, nausea, loss of appetite, bloating and diarrhea.
The participants were randomized across three treatment groups, two of which treated patients with AK002 in various doses. The third group was given a monthly placebo drug.
According to Allakos' Aug. 5 press release, both AK002 treatment arms showed statistically significant disease symptom improvements compared to the placebo arm. Patients treated with AK002 saw at least a 92% reduction in eosinophil counts in the small intestine. Eosinophils are a type of white blood cell, which in high volumes denotes inflammation. In comparison, placebo-treated participants saw a 10% increase in eosinophil count.
The trial also met its secondary goals, which included treatment response and patient-reported symptom changes. Allakos said 68% to 70% of patients in the AK002 treatment arms responded to the drug, meaning they experienced a minimum 75% reduction in eosinophils and a greater than 30% reduction in symptoms. In the placebo arm, 5% of patients responded.
Allakos-treated patients reported a 49% to 58% reduction in symptoms, while placebo-treated patients saw a 24% reduction.
In an exploratory analysis, 13 out of the 14 patients who also had eosinophilic esophagitis, which affects the esophagus, demonstrated a statistically significant decrease in esophageal eosinophil counts. Dysphagia, or difficulty swallowing, was also reduced by 53% in AK002-treated patients, versus 17% with placebo.
AK002 was generally well-tolerated by patients, according to Allakos. Overall, 9% of AK002-treated patients reported serious side effects compared to 14% of those in the placebo arm. Mild to moderate infusion-related reactions, such as flushing, dizziness, headache and nausea, were more common with AK002, with 60% of treated participants experiencing these side effects compared to 23% of placebo-treated patients. Allakos reported one serious infusion-related adverse event, which was resolved within 24 hours.
Further studies in eosinophilic gastritis, eosinophilic gastroenteritis and eosinophilic esophagitis will begin in the first fiscal quarter of 2020, Allakos said.