scPharmaceuticals Inc. shares dropped 10.6% in premarket trade on Wednesday after the Food and Drug Administration failed to approve the company’s edema treatment. The therapy, Furoscix, was intended for edema, or fluid overload, in heart failure patients. The regulator said more human factors studies, device modifications and possibly a clinical validation study were needed. The company said it plans to address the issues and bring the product to market. scPharmaceuticals shares have dropped 56% over the last three months, compared with a 0.8% rise in the S&P 500 and a 1.3% rise in the Dow Jones Industrial Average .