This week, the overall grades of 11 biotechnology stocks are lower, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, CEL-SCI Corporation (CVM) falls to a D (“sell”), worse than last week’s grade of C (“hold”). 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.

Slipping from a C to a D rating, EPIRUS Biopharmaceuticals, Inc. (EPRS) takes a hit this week. The stock also rates an F in Earnings Revisions. For more information, get Portfolio Grader’s complete analysis of EPRS stock.

Ohr Pharmaceutical Inc (OHRP) experiences a ratings drop this week, going from last week’s 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. To get an in-depth look at OHRP, get Portfolio Grader’s complete analysis of OHRP stock.

Trius Therapeutics, Inc. (TSRX) earns a D this week, falling from last week’s grade of C. 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.

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 Sept. 4, 2015, 20.6% of outstanding Synergy Pharmaceuticals, Inc. shares were held short. To get an in-depth look at SGYP, get Portfolio Grader’s complete analysis of SGYP stock.

Verastem, Inc. (VSTM) earns an F this week, moving down from last week’s grade of D. 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 Sept. 4, 2015, 11.2% of outstanding Verastem, Inc. shares were held short. For more information, get Portfolio Grader’s complete analysis of VSTM stock.

Celldex Therapeutics, Inc. (CLDX) is having a tough week. The company’s rating falls 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 Sept. 4, 2015, 16.9% of outstanding Celldex Therapeutics, Inc. shares were held short. To get an in-depth look at CLDX, get Portfolio Grader’s complete analysis of CLDX stock.

Trevena, Inc. (TRVN) gets weaker ratings this week as last week’s C drops to a D. The stock gets F’s in Equity and Cash Flow. Trade volume is up 2339.4% from the previous week. For more information, get Portfolio Grader’s complete analysis of TRVN stock.

The rating of Applied Genetic Technologies Corp. (AGTC) declines this week from a C to a D. The stock gets F’s in Earnings Surprise, Equity and Cash Flow. To get an in-depth look at AGTC, get Portfolio Grader’s complete analysis of AGTC stock.

The rating of Avalanche Biotechnologies Inc (AAVL) slips from a C to a D. The stock gets F’s in Equity and Cash Flow. For more information, get Portfolio Grader’s complete analysis of AAVL stock.

This week, Tokai Pharmaceuticals, Inc. (TKAI) drops from a C to a D rating. The stock gets F’s in Equity and Cash Flow. As of Sept. 4, 2015, 13.1% of outstanding Tokai Pharmaceuticals, Inc. shares were held short. To get an in-depth look at TKAI, get Portfolio Grader’s complete analysis of TKAI 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.