What happened

Shares of INmune Bio (NASDAQ:INMB) soared as much as 19.4% in early trading on Thursday. However, the stock quickly gave up those gains and then some. INmune's shares were sinking 17% as of 3:39 p.m. EST. 

The big jump came after the biotech announced encouraging results from a phase 1b study evaluating XPro1595 in treating Alzheimer's disease. However, the stock promptly fell throughout the morning -- probably due in part to profit-taking. Some investors were likely wary about banking too much on success for XPro1595 in light of the numerous Alzheimer's disease candidates that once seemed promising but ultimately flopped. 

Alzheimer's disease on a form next to X-rays, a pen, a  syringe, and pills

Image source: Getty Images.

So what

It's not all that surprising to see such high volatility for a clinical-stage biotech stock. Even good news can sometimes fail to keep investors excited for very long.

INmune's results did seem to be pretty good, though. The company reported that data from the phase 1b study suggested that patients who received XPro1595 experienced decreasing biomarkers of neuroinflammation based on several measures and assays. INmune's head of neurosciences, C.J. Barnum, said that this improvement in biomarkers "gives us great confidence that XPro1595 is having the desired effect in the CNS [central nervous system]."

However, these results are still very early. INmune still hasn't conclusively established that XPro1595 improves the condition of patients with Alzheimer's disease. More testing will be required.

Now what

INmune plans to move forward to conduct the additional testing that's needed. CEO RJ Tesi stated that the biotech intends to initiate a phase 2 clinical study of XPro1595 this year. The results from the phase 1b study will assist INmune in finalizing the design for the phase 2 study. 

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