The only drug approved by the FDA for the acute treatment of strokes is tPA. tPA is the "clot busting" drug that must be given very shortly after a stroke has started. It's major side effect is bleeding which may occur in the brain. If this happens, additional damage to the brain can occur. Because of the short time window during which it may be administered, many people don't get to the hospital soon enough to qualify for use of tPA.

A novel new function may breathe new life into an old drug. Minocycline, an antibiotic used to treat acne, may be an alternative treatment for stroke. It is a semisynthetic cousin of tetracycline. It has been shown to have neuroprotective effects in animal models of multiple sclerosis (MS), Parkinson disease, Huntington disease and ALS (Lou Gehrig's disease). The mechanisms responsible for the death of nerve cells in these diseases share many similarities with cell death pathways in stroke. This prompted investigators to evaluate minocycline in a rodent stroke model. Pyramidal neuron (a type of nerve cell) survival increased from 10 to 77% after administration of minocycline. In another animal stroke model, even when administered 48 hours after a stroke developed, minocycline reduced the size of the stroke.

The proposed mechanisms of minocycline's actions appear to have nothing to do with its antibiotic effects. It seems to have significant anti-inflammatory activities as well as a novel ability to inhibit what are referred to as cell death cascades (that cause nerve cells to essentially self destruct under adverse circumstances) triggered by stroke-like events.

In an open-label, evaluator-blinded study done at Edith Wolfson Hospital in Holon, Israel, minocycline was given to stroke patients for five days. It was started between 6 and 24 hours after onset of a stroke. One hundred fifty-one patients were enrolled in the study. They were followed for 90 days. Recovery rate and final neurological status were evaluated. Improvement was noted as early as day 7. No evidence of recurrent stroke or hemorrhage was noted during the follow-up period. Patients had significantly improved outcome with minocycline treatment in this open label study.

It appears that the beneficial actions of minocycline, especially its antagonism of cell death pathways, which are not engaged acutely during a stroke, make it a potentially useful candidate for stroke therapy with a wider therapeutic time window. Based on these promising preliminary findings, Dr. David Hess at the Medical College of Georgia will further study the efficacy of minocycline in acute stroke in a prospective double-blinded human trial. The current focus of the study is to determine drug safety, optimal dosing regimens and during of therapy.

If previous findings are upheld, minocycline may become a new "standard" therapy for patients experiencing symptoms of acute stroke.