Vanda is developing tasimelteon as a treatment for a rare sleep disorder which affects blind people. Vanda shares fell in June after questions were raised about the company's clinical development of tasimelteon, raising the risk that the drug would be rejected by FDA. No. 4: Stemline Therapeutics ( STML) STML data by YCharts
Stemline is developing drugs which target cancer stem cells. The company's shares rose following the presentation of clinical data at the American Society of Clinical Oncology annual meeting in early June. No. 3: Immunomedics ( IMMU) IMMU data by YCharts
Immunomedics will be presenting results from a phase I study of the experimental radio-labeled monoclonal antibody Clivatuzumab tetraxetan at a medical meeting, July 3-6. No. 2: Acadia Pharmaceuticals ( ACAD) ACAD data by YCharts
Acadia continues to be one of the strongest-performing stocks in the biotech sector this year, supported by investor excitement for the company's Parkinson's psychosis drug pimavanserin. No. 1: Clovis Oncology ( ACAD) CLVS data by YCharts
Clovis is not only the best-performing stock in the second quarter, but it's also No. 1 for all of 2013 so far. Why? The experimental lung cancer drug CO-1686. Not all bio-pharma stocks enjoyed success in the second quarter. The worst-performing stocks for the June quarter were: No. 5: Cardium Therapeutics ( CXM) -56%
No. 4: Aveo Pharmaceuticals ( AVEO) -66%
No. 3: Infinity Pharmaceuticals ( INFI) -67%
No. 2: Echo Therapeutics ( ECTE) -68% No. 1: GenVec ( GNVC): -75% -- Reported by Adam Feuerstein in Boston. Follow Adam Feuerstein on Twitter.