(CORRECTED: See below.)

Featured companies: VistaGen Therapeutics, MindWeavers, Cutanea Life Sciences, Heptares Therapeutics

vistagen-logo.jpgVistaGen raises $3.75M for stem-cell based drug discovery — South San Francisco, Calif.-based VistaGen Therapeutics, a biotech that uses human embryonic stem cells to discover new drugs, raised $3.75 million in a bridge financing as it prepares to raise up to $20 million in a fourth round, VentureWire reports (subscription required). Montaur Capital Partners provided the funding.

VistaGen, founded in 1998, isn’t your typical stem-cell company. Where companies ranging from Geron and Advanced Cell Technology to Novocell aim to use the controversial cells — which must be derived from five-day-old embryos in a destructive process — directly as therapies to help regenerate damaged organs, VistaGen merely grows stem-cell cultures in its labs and uses those cultures to discover and run preliminary safety tests on drug candidates.

The embryonic cells are capable of “differentiating” into any type of cell in the body, which VistaGen says makes them valuable for determining how an experimental drug molecule will interact with living human tissue. The company uses its stem-cell “screens” to identify promising small-molecule drugs (that is, compounds that can be swallowed rather than injected) and to determine what side effects they might cause once ingested. Over time, VistaGen suggests, it might develop screens for drugs that trigger stem cells’ regenerative powers, potentially inducing cellular repair in conditions such as heart disease or diabetes.

For now, however, VistaGen’s lead drug candidate is a relatively prosaic compound called AV-101 that the company plans to begin testing against epilepsy later this year. AV-101 is a “prodrug” — a molecule that’s converted into an active form by the body’s natural metabolism — that turns into a neuroinhibitor once it reaches the brain. In addition to epilepsy, VistaGen suggests that the drug may also have uses in stroke, neuropathic pain and neurodegenerative diseases such as Alzheimer’s disease. For more detailed info, see the company’s Web site here and here.

mindweavers-logo.jpgOxford’s MindWeavers raises $1.1M for mind-altering software — MindWeavers, an Oxford, England-based software company that develops software designed to improve mental function, raised $1.1 million (£558,000) through City and Merchant Group. Next year, the company hopes to raise up to £1 million with a listing on London’s Plus Markets electronic exchange.

MindWeavers develops its programs based on neuroscience research from Oxford University, which spun out the company in 2000. Its first product was Phonomena, a interactive game for children that the company says builds auditory discrimination and language skills. Several other programs are designed to improve “neuroplasticity” and to stimulate brain activity in middle-aged and elderly people in order to ward off age-related cognitive decline. VentureWire has more.

cutanea-logo.jpgSkin-care firm Cutanea raises “millions” in convertible debt — Cutanea Life Sciences, a Cambridge, Mass., specialty pharmaceutical company focused on dermatology, raised a “multi-million” dollar round of convertible debt, VentureWire reports. Institutional investors such as Nexus Medical Partners provided the funding. Cutanea licenses neglected or cast-off experimental drugs from universities or other companies and runs them through human tests.

Heptares Therapeutics spins out of Britain’s MRC — The MRC Laboratory of Molecular Biology has spun out a new company, Heptares Therapeutics, with undisclosed seed funding from MVM Life Sciences Partners. The company will focus on drugs for diseases of the nervous system and metabolism. (Hat tip: PE Hub.)

CORRECTION: Due to incorrect information supplied by VentureWire, the VistaGen Therapeutics item originally stated that Montreux Equity Partners provided funding. In fact, Montaur Capital Partners led the funding. The VentureWire correction is here.