Targeted cancer therapy is a revolution in drug company research, and Rexahn Pharmaceuticals, Inc. recent recipient of a notice of allowance from the US Patent and Trademark Office for a new delivery platform, might one day join the leagueof bigger players.

The S&P 500 fell 29 points, or 1.5%, to 1969. The Nasdaq NDAQ -1.61% Composite Index declined 83 points, or 1.8%, to 4472.

Now that Rexahn's partnership with Teva fell apart, it appears the company is looking for a new partner for its RX-3117 cancer compound.