This week, the ratings of 10 biotechnology stocks on Portfolio Grader are down. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

CEL-SCI Corporation (CVM) is on the decline this week, earning a D (“sell”) after receiving a C (“hold”) last week. CEL-SCI is developing new immune system based treatments for cancer and infectious diseases. In Portfolio Grader’s specific subcategories of Equity and Cash Flow, CVM also gets F’s. For more information, get Portfolio Grader’s complete analysis of CVM stock.

This week, EPIRUS Biopharmaceuticals, Inc. (EPRS) drops from a C to a D rating. The stock also gets an F in Earnings Revisions. To get an in-depth look at EPRS, get Portfolio Grader’s complete analysis of EPRS stock.

The rating of Ohr Pharmaceutical Inc (OHRP) declines this week from a C to a D. Ohr Pharmaceutical develops pharmaceuticals for wound care and to treat cachexia. The stock gets F’s in Earnings Revisions and Equity. For more information, get Portfolio Grader’s complete analysis of OHRP stock.

This is a rough week for Trius Therapeutics, Inc. (TSRX). The company’s rating falls to D from the previous week’s C. Trius Therapeutics is a biopharmaceutical company. The stock gets F’s in Earnings Growth, Earnings Momentum and Equity. Cash Flow and Sales Growth also get F’s. To get an in-depth look at TSRX, get Portfolio Grader’s complete analysis of TSRX stock.

Slipping from a C to a D rating, Vical Incorporated (VICL) takes a hit this week. Vical researches and develops biopharmaceutical products based on its patented DNA delivery technologies for the prevention and treatment of serious or life-threatening diseases. The stock gets F’s in Equity and Cash Flow. For more information, get Portfolio Grader’s complete analysis of VICL stock.

Tenax Therapeutics, Inc. (TENX) earns an F (“strong sell”) this week, moving down from last week’s grade of D (“sell”). The stock receives F’s in Earnings Momentum, Earnings Revisions and Equity. Cash Flow and Sales Growth also get F’s. To get an in-depth look at TENX, get Portfolio Grader’s complete analysis of TENX stock.

Synergy Pharmaceuticals, Inc.’s (SGYP) rating weakens this week, dropping to an F versus last week’s D. Synergy Pharmaceuticals is a biopharmaceutical company focused on the development of drugs to treat gastrointestinal disorders and diseases. The stock gets F’s in Equity and Cash Flow. As of May 27, 2015, 16.3% of outstanding Synergy Pharmaceuticals, Inc. shares were held short. For more information, get Portfolio Grader’s complete analysis of SGYP stock.

The rating of Verastem, Inc. (VSTM) slips from a D to an F. Verastem is a biopharmaceutical company which is focused on discovering and developing novel drugs that selectively target cancer stem cells in breast and other cancers along with proprietary companion diagnostics. The stock gets F’s in Equity and Cash Flow. As of May 27, 2015, 10.2% of outstanding Verastem, Inc. shares were held short. To get an in-depth look at VSTM, get Portfolio Grader’s complete analysis of VSTM stock.

This week, Celldex Therapeutics, Inc.’s (CLDX) rating worsens to a D from the company’s C rating a week ago. Celldex Therapeutics is engaged in the discovery, development and commercialization of products that harness the human immune system to prevent and treat disease. The stock also gets an F in Equity. As of May 27, 2015, 16.9% of outstanding Celldex Therapeutics, Inc. shares were held short. For more information, get Portfolio Grader’s complete analysis of CLDX stock.

Trevena, Inc. (TRVN) experiences a ratings drop this week, going from last week’s C to a D. The stock gets F’s in Equity and Cash Flow. To get an in-depth look at TRVN, get Portfolio Grader’s complete analysis of TRVN stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.