The ratings of nine biotechnology stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

CEL-SCI Corporation’s (CVM) rating falls to a D (“sell”) this week, down from C (“hold”) the week prior. 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. To get an in-depth look at CVM, get Portfolio Grader’s complete analysis of CVM stock.

This week, EPIRUS Biopharmaceuticals, Inc.’s (EPRS) rating worsens to a D from the company’s C rating a week ago. The stock also gets an F in Earnings Revisions. For more information, get Portfolio Grader’s complete analysis of EPRS stock.

Ohr Pharmaceutical Inc (OHRP) earns a D this week, moving down from last week’s grade of C. Ohr Pharmaceutical develops pharmaceuticals for wound care and to treat cachexia. The stock gets F’s in Earnings Revisions and Equity. To get an in-depth look at OHRP, get Portfolio Grader’s complete analysis of OHRP stock.

The rating of Trius Therapeutics, Inc. (TSRX) slips from a C to a D. Trius Therapeutics is a biopharmaceutical company. The stock receives F’s in Earnings Growth, Earnings Momentum and Equity. Cash Flow and Sales Growth also get F’s. For more information, get Portfolio Grader’s complete analysis of TSRX stock.

Vical Incorporated (VICL) earns a D this week, falling from last week’s grade of C. 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. To get an in-depth look at VICL, get Portfolio Grader’s complete analysis of VICL stock.

Synergy Pharmaceuticals, Inc.’s (SGYP) rating falls this week to an F (“strong sell”), down from last week’s D (“sell”). 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 Aug. 5, 2015, 23.6% of outstanding Synergy Pharmaceuticals, Inc. shares were held short. For more information, get Portfolio Grader’s complete analysis of SGYP stock.

This week, Verastem, Inc. (VSTM) drops from a D to an F rating. 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 Aug. 5, 2015, 12.5% 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.

The rating of Celldex Therapeutics, Inc. (CLDX) declines this week from a C to a D. 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 Aug. 5, 2015, 16.6% of outstanding Celldex Therapeutics, Inc. shares were held short. For more information, get Portfolio Grader’s complete analysis of CLDX stock.

Trevena, Inc.’s (TRVN) rating weakens this week, dropping to a D versus last week’s C. 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.