Pfizer has decided to stop the recruitment of patients into the EMPHASIS-HF drug trial early. That headline should raise some eyebrows, since it means one of two possible outcomes: Early results are either very good or very, very bad.
Thankfully, the results seem to be very good! According to the press release (a 5 page .pdf file) the study reached its “primary efficacy endpoint” early – in other words, the investigators proved what they were looking for. Taking Eplerenone (also known as Inspra) in conjunction with recommended Heart Failure standards of care, lowers incidence of hospitalization and/or death in patients with mild to moderate heart failure. The adverse events (things that went wrong) included a higher level of potassium in 8% of the patients taking Eplerenone and 4% had renal impairment. Renal impairment means that their kidneys stopped functioning, but that condition can occur because of heart failure also. Apparently the incidence of Renal impairment caused by the new drug is not much different from the number of kidney problems cause just by having heart failure. The Clinical Trial was a double-blind test, which lends it even more credibility, as neither the subject or the investigator knew which drug was being used – the Eplerenone or a harmless placebo. When carried out correctly, a double-blind test prevents either the subject or the investigator from being biased.
So what happens now? Don’t expect to be getting a prescription for Eplerenone, the company does not have a license to sell to human subjects. The study was a small one – only 3100 people, if it had reached full enrollment. All patients, no matter which drug they are on, will be informed of the decision to close the study early. Pfizer has asked for permission to move all consenting patients into a larger study of the drug.
Sometimes medical research comes in small increments – baby steps. But you have to walk before you can run!