District Judge Lorna G. Schofield
Defendant moved to preclude the testimony of plaintiff’s medical expert and moved for summary judgment on products liability action arising from his ingestion of Risperdal, an anti-psychotic medication manufactured by defendant. Plaintiff alleged that use of Risperdal caused him to develop gynecomastia. Plaintiff’s expert proposed to testify that Risperdal was a substantial contributing factor to plaintiff’s gynecomastia and that other potential causes, including puberty, obesity, or marijuana use, were not the cause or the only cause of plaintiff’s gynecomastia. The court denied defendant’s motion, finding that plaintiff’s expert’s qualifications provided circumstantial evidence of reliability. The court further found that plaintiff’s expert’s causation opinion was reliable as it was arrived at using differential diagnosis and supported by multiple studies addressing the relationship between medication use and gynecomastia. The court further found that defendant’s objections went to the weight rather than the reliability of the opinion. Because plaintiff’s expert’s opinion raised a factual dispute, the court denied summary judgment to defendant on plaintiff’s warranty breach claim but granted it on the failure to warn claim due to the lack of causation.