Drug firms are vying to create the first inhaled version of insulin, which could deliver therapy more simply and effectively than needles to millions of diabetics. Rita Vanbever’s work might give Eli Lilly the edge. An associate professor of pharmaceutical technology at the Catholic University of Louvain in Belgium, Vanbever provided much of the chemical expertise that les to low-toxicity porous aerosol particles that carry insulin deep into the lungs. The particles do not clump, as earlier, smaller, and denser particles did, and they can be used with both fast-acting and long-actibg drugs. Cambridge, MA, drug firm Alkermes has licensed Vanbever’s techniques and is using them in partnership with Eli Lilly to develop inhaled human growth hormone in addition to insulin. Barriers remain; Vanbever discovered that human immune cells known as macrophages in the lung’s air sacs prevent up to 50 percent of such protein therapeutics from being absorbed into the bloodstream. But she is confident that her delivery methods will ultimately shrink that percentage significantly.