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Greetings, An article on problems and progress in delivery of medicines across the blood-brain barrier appeared in the science section (page F1) of the March 31 issue of the New York Times. Although the article deals mainly with delivery of drugs to treat brain tumors, some points are made that are relevant to PD, so here is my summary of what the article contains regarding the latter. There is a general discussion of the function of the blood-brain barrier, to provide a "stable environment for the brain" by controlling which substances in the bloodstream can enter it. This control mechanism is often an obstacle to drug therapy, and the development of drug delivery mechanisms can be more difficult than the development of the drugs themselves. Yet, academic and government researchers are quoted as saying, "major drug companies do not pay enough attention to the blood-brain barrier," because "they're hoping someone else will solve the problem or they can get around it or it won't be an issue." Some methods of getting around the blood-brain barrier to deliver cancer drugs - e.g., transient forced openings - are risky and not suitable for treatment of PD. But another method, installing pumps in patients' skulls to squirt a steady stream of cancer-killing agents, used by a team at the National Cancer Institute, is forseen as having future use for delivery of gene therapy and growth factors to induce nerve regeneration in patients with PD and Alzheimer's. Dr. William Pardridge, a researcher at UCLA, favors a pharmacological delivery method which he calls the "Trojan horse". This involves linking drug molecules to other molecules which can pass the barrier. Dr. Pardridge and his colleagues are investigating the use of a substance that resembles insulin as the transporter. Some implications which I think can be drawn from the article: - research and development of drug delivery methods to the brain, although not PD specific, requires NIH funding and ought to be of as much concern to the PD community as is the developement of anti-PD drugs themselves; - it seems that we are several years away from a "Trojan horse" for new PD drugs, since the UCLA researchers are now trying out their approach on monkeys. Phil Tompkins Hoboken NJ 60/9