Amid a surging U.S. stock market that is helping fund drug developers and other growth companies, five Philadelphia biotech firms attracted hundreds of millions of dollars in out-of-town investment and acquisition capital last week, notes Martin Lehr, CEO and cofounder of Context Therapeutics, a Drexel University spin-off.

"Amazing," says Lehr, whose own firm is developing Sigma1, a drug for use against cancer and other diseases, and is funded by grants from the National Cancer Institute and wealthy investors.

The deals include:

–  Up to $425 million for InfaCare Pharmaceutical Corp., the 16-year-old, Trevose-based developer of Stanate, a treatment that helps babies with severe jaundice (which turns them yellow) avoid blood transfusions and hospitals. Founder Robert A. Vukovich, 73, sold the company to Mallinckrodt Inc. for an $80 million upfront payment, plus up to $345 million in future payments if Stanate meets sales projections.

– $330 million (net proceeds) in a secondary stock offering for Spark Therapeutics. The University City gene therapy developer, based on Katherine A. High's work at Children's Hospital of Philadelphia, hired JPMorgan and Goldman Sachs to sell more stock; they priced 4.4 million shares at $76 each. Spark's current clinical trials include treatments for hemophilia and a rare eye disease; its commercial partners include Pfizer.

– $62 million in third-round venture-capital fund-raising by Complexa Inc., the Radnor firm run by former AstraZeneca and startup veteran CEO Joshua Tarnoff (a LaSalle graduate) and medical head Diane K Jorkasky (formerly of Endo and SmithKline, and a veteran of the Penn Medicine staff). Complexa said it will use the money to boost clinical development of CXA-10, which fights an "orphan" kidney disease.

– $42 million in second-round venture funding from Versant Ventures, Foresite Capital, and Abingworth for VenatoRx Pharmaceuticals Inc., a Malvern developer of antibiotics for drug-resistant infections, run by Christopher J. Burns, formerly of Novartis' Protez division. Versant also boasts a National Institutes of Health grant and funding from London-based Wellcome Trust.

-$12.7 million from New Ventures III and earlier investors for Enterin, a Philadelphia firm headed by Georgetown University transplant specialist and Magainin Pharmaceuticals Inc. founder Michael A. Zasloff. Enterin is developing ENT-01, a treatment it says "repairs the dysfunctional gut-brain axis" in Parkinson's and other neurodegenerative disease patients, to relieve constipation, among other conditions.