NEW YORK (TheStreet) -- Jefferies downgraded BioCryst Pharmaceuticals (BCRX - Get Report) stock to "hold" from "buy" and cut its price target to $2 from $14, after the company announced disappointing trial results yesterday for its treatment for angioedema attacks.

The biotechnology company's treatment is known as avoralstat and is designed for hereditary angioedema attacks, which cause swelling in the body.

"We believe it remains possible their higher-exposure solid-tablet avoralstat formulation or improved-profile next-gen kallikrein inhibitor '7353 could ultimately perform better, but given the higher overall risk (lower prob. of success to 30%) and pushed-out timelines (~1.5y) we believe it is difficult to continue to recommend shares pending further clarity," Jefferies said in an analyst note.

Shares of BioCryst are rebounding by 9.55% to $1.95 on heavy trading volume on Tuesday afternoon.

About 3.61 million of the company's shares were traded by this afternoon, compared to its average volume of 1.06 million shares per day.

The Durham-based company designs, optimizes and develops small molecule drugs that block enzymes involved in the pathogenesis of diseases, with a focus on the treatment of rare diseases.

Separately, TheStreet Ratings Team has a "Sell" rating with a score of D- on the stock.

This is driven by multiple weaknesses, which should have a greater impact than any strengths, and could make it more difficult for investors to achieve positive results compared to most of the stocks covered by the team.

The company's weaknesses can be seen in multiple areas, such as its unimpressive growth in net income, disappointing return on equity, weak operating cash flow, generally disappointing historical performance in the stock itself and feeble growth in its earnings per share.

Recently, TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this articles's author.

You can view the full analysis from the report here: BCRX

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