A preview of the emerging health care companies profiled in the current issue of Start-Up. This month's profile group, "The Drug Delivery Road Gets Tougher," features profiles of ActoGeniX, Atacama Labs, Glide Pharma and Mimetic Solutions. Plus these Start-Ups Across Health Care: Light Dimensions, Relyspa, Stentys and Thrombotargets.

A polymer that responds to a specific protein, peptide, or other biological molecule by rupturing is the underpinning technology for Mimetic Solutions. The company's Affinimers can release encapsulated drugs at specific locations or times. The polymers become "activated" when they interact with the biological molecule to which they've been engineered to respond-insulin, for example, in the presence of a certain amount of glucose. This sets off a series of interactions within the polymer that ultimately lead it to decompose and release its payload.

While making money in drug delivery has always been tougher than its boosters have promised, this year's been ugly in new and disturbing ways. The key lessons of Pfizer's abandonment of inhaled insulin and Impax's patent assault on Endo's Opana are that partners are less reliable; the products need to be medically superior to existing ones, not simply more convenient; and generic companies are making inroads into the main bastion of drug-delivery success -- spec pharma.

In Vivo briefly summarizes the technologies of these recently founded companies: Azano Pharmaceuticals, GeNeuro, LaamScience, Mimetic Solutions, Tragara Pharmaceuticals, and Wireless bioDevices.