BOSTON ( TheStreet) --With December upon us, it's a good time to start thinking ahead to what 2010 has in store for biotech investors. In that vein comes a report this morning from Leerink Swann highlighting a series of "unexpected" events that could have a big impact on biopharma in 2010.

The research firm isn't predicting that these surprise events will happen, just that the events are all plausible, unexpected or not anticipated, and would have a big impact on share price.

Topping Leerink's list of potential surprise events for 2010 is the development of a test to predict which multiple sclerosis patients are at high risk for developing the serious brain infection progressive multifocal leucoencephalopathy, or PML.

A predictive test for PML would allow Biogen Idec ( BIIB - Get Report) and Elan ( ELN) to identify patients who would benefit the most from their multiple sclerosis drug Tysabri.

"BIIB shares alone could appreciate by 35%-plus (derived by assigning growth-multiple of 13x on 2012 projected earnings of $4.75 if Tysabri were to grow as opposed to the decline which we currently model) if investors gain confidence in Tysabri's growth potential," Leerink says.

Other potential surprises for 2010 from Leerink include:
  • Competitors to Vertex Pharmaceuticals' (VRTX - Get Report) hepatitis C drug telaprevir are shelved or set back due to toxicity issues.
  • Merck (MRK) develops a successful preventative vaccine against Staph infection.
  • Inspire Pharmaceuticals (ISPH) gets its eye drug Prolacria approved by the Food and Drug Administration.
  • FDA pulls older, abuse-able opioids from market, benefiting newer, abuse-resistant painkillers like King Pharmaceuticals' (KG) Embeda.
  • Positive phase III results from Elan and Pfizer's (PFE) Alzheimer's disease drug bapineuzumab.
  • Fresenius (FMS) buys Affymax (AFFY) to enter the anemia drug treatment market for chronic kidney disease patients. (Also a potential negative for Amgen (AMGN).)
  • Onyx Pharmaceutical's (ONXX) second phase III study of Nexavar in first-line, non-small cell lung cancer is a success.
  • Momenta Pharmaceuticals (MNTA - Get Report) receives FDA approval for a generic version of the blood thinner Lovenox.
  • Biodel's (BIOD) rapid acting insulin Viaject receives FDA approval.

-- Reported by Adam Feuerstein in Boston

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