Shares of MediciNova declined after topline results from a Phase 2 trial for the company's potential treatment for hypertriglyceridemia and nonalcoholic fatty liver disease did not show statistical significance in reducing liver fat versus a placebo.

The stock fell 13% to $2.25 in premarket trading Monday. As of Friday's market close, shares were up 97% year to date.

MediciNova said patients treated with MN-001 showed a decrease in serum triglycerides and increases in serum high-density lipoprotein cholesterol and HDL particle concentration that were all statistically significant compared with the placebo group.

However, the study did not observe a statistically significant difference in liver fat reduction between the treatment and placebo groups, though the treatment group continued to show a decrease from baseline value at week 24, MediciNova said.

The company had said last year that the study's co-primary endpoints would include change from baseline in liver fat content measured by a controlled attenuation parameter score at week 24, and change from baseline in fasting serum triglycerides over the same timeline.

MediciNova said the results provide a basis for further evaluation of MN-001 in metabolic and cardiovascular diseases. It plans to continue analyzing the study data and said it would assess the next stage of clinical development.