The ratings of 13 Biotechnology stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, Kite Pharma, Inc.’s (KITE) rating worsens to a D from the company’s C rating a week ago. The company also gets F’s in earnings revisions, earnings momentum, and return on equity. For more information, get Portfolio Grader’s complete analysis of KITE stock.

Otonomy, Inc. (OTIC) earns a D this week, moving down from last week’s grade of C. The company also gets F’s in earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of OTIC stock.

Versartis, Inc. (VSAR) is having a tough week. The company’s rating falls from a C to a D. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of VSAR stock.

Slipping from a D to a F rating, Halozyme Therapeutics, Inc. (HALO) takes a hit this week. Halozyme Therapeutics, Inc. is a biopharmaceutical company developing products for the diabetes, cancer, dermatology and drug delivery markets. The company also gets F’s in return on equity. For more information, get Portfolio Grader’s complete analysis of HALO stock.

MiMedx Group, Inc.’s (MDXG) rating weakens this week, dropping to a D versus last week’s C. MiMedx Group, Inc. operates as a medical device company. The company also gets F’s in earnings growth, earnings surprise, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of MDXG stock.

This is a rough week for ImmuCell Corporation (ICCC). The company’s rating falls to D from the previous week’s C. ImmuCell Corporation is engaged in the development, manufacture and sale of products that improve the health and productivity of cows for the dairy and beef industry. The company also gets F’s in earnings momentum. For more information, get Portfolio Grader’s complete analysis of ICCC stock.

This week, Sorrento Therapeutics, Inc. (SRNE) drops from a D to a F rating. The company also gets F’s in earnings surprise, earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of SRNE stock.

Tokai Pharmaceuticals, Inc. (TKAI) experiences a ratings drop this week, going from last week’s D to a F. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of TKAI stock.

T2 Biosystems, Inc. (TTOO) declines this week from a D to a F. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of TTOO stock.

Cara Therapeutics Inc (CARA) gets weaker ratings this week as last week’s D drops to a F. The company also gets F’s in sales growth, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of CARA stock.

Catabasis Pharmaceuticals Inc (CATB) slips from a D to a F this week. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of CATB stock.

CorMedix Inc.’s (CRMD) rating weakens this week, dropping to a D versus last week’s C. CorMedix Inc. is a development-stage pharmaceutical company that seeks to fulfill selected, significant unmet medical needs in the therapeutic areas at the crossroads of cardiac and kidney (renal) disease. The company also gets F’s in earnings surprise, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of CRMD stock.

Galectin Therapeutics Inc. (GALT) is having a tough week. The company’s rating falls from a D to a F. Galectin Therapeutics Inc. is a drug development company. The company also gets F’s in earnings revisions, earnings surprise, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of GALT 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.