The overall ratings of 33 Biotechnology stocks are down on Portfolio Grader this week. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Vertex Pharmaceuticals Incorporated (VRTX) experiences a ratings drop this week, going from last week’s C to a D. Vertex Pharmaceuticals Incorporated is engaged in the business of discovering, developing and commercializing small molecule drugs for the treatment of serious diseases. The company also gets F’s in earnings revisions and return on equity. For more information, get Portfolio Grader’s complete analysis of VRTX stock.

BioMarin Pharmaceutical Inc. (BMRN) earns a D this week, moving down from last week’s grade of C. BioMarin Pharmaceutical Inc. develops and commercializes innovative pharmaceuticals for serious diseases and medical conditions. The company also gets F’s in earnings growth, earnings surprise, and return on equity. For more information, get Portfolio Grader’s complete analysis of BMRN stock.

Spark Therapeutics, Inc.’s (ONCE) rating weakens this week, dropping to a D versus last week’s C. The company also gets F’s in return on equity. For more information, get Portfolio Grader’s complete analysis of ONCE stock.

Alkermes Plc (ALKS) declines this week from a D to a F. Alkermes Plc is a fully integrated biotechnology company committed to developing medicines that will improve patients’ lives. The company also gets F’s in earnings growth, earnings surprise, earnings momentum, and return on equity. For more information, get Portfolio Grader’s complete analysis of ALKS stock.

This week, Portola Pharmaceuticals, Inc. (PTLA) drops from a C to a D rating. The company also gets F’s in return on equity. For more information, get Portfolio Grader’s complete analysis of PTLA stock.

This week, Genomic Health, Inc.’s (GHDX) rating worsens to a D from the company’s C rating a week ago. Genomic Health, Inc. is a life science company, which is focused on the development and commercialization of genomic-based clinical diagnostic tests for cancer that allow physicians and patients to make individualized treatment decisions. The company also gets F’s in earnings revisions and return on equity. For more information, get Portfolio Grader’s complete analysis of GHDX stock.

Slipping from a D to a F rating, Newlink Genetics Corporation (NLNK) takes a hit this week. Newlink Genetics Corporation is a biopharmaceutical company focused on discovering, developing, and commercializing novel immunotherapeutic products to improve cancer treatment options for patients and physicians. The company also gets F’s in earnings surprise, earnings momentum, and return on equity. For more information, get Portfolio Grader’s complete analysis of NLNK stock.

This is a rough week for Cellular Biomedicine Group, Inc. (CBMG). The company’s rating falls to D from the previous week’s C. The company also gets F’s in return on equity. For more information, get Portfolio Grader’s complete analysis of CBMG stock.

uniQure N.V. (QURE) gets weaker ratings this week as last week’s C drops to a D. 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 QURE stock.

TG Therapeutics, Inc. (TGTX) slips from a C to a D this week. TG Therapeutics, Inc. is a clinical-stage biopharmaceutical company focused on the acquisition, development and commercialization of innovative pharmaceutical products for the treatment of cancer and other underserved therapeutic needs. 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 TGTX stock.

Celldex Therapeutics, Inc. (CLDX) is having a tough week. The company’s rating falls from a D to a F. Celldex Therapeutics, Inc. is engaged in the discovery, development and commercialization of products that harness the human immune system to prevent and treat disease. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of CLDX stock.

Slipping from a C to a D rating, Trillium Therapeutics Inc. (TRIL) takes a hit this week. 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 TRIL stock.

Achillion Pharmaceuticals, Inc. (ACHN) slips from a C to a D this week. Achillion Pharmaceuticals, Inc. focuses on the discovery, development and commercialization of innovative treatments for infectious diseases. The company also gets F’s in earnings revisions. For more information, get Portfolio Grader’s complete analysis of ACHN stock.

Tobira Therapeutics, Inc. (TBRA) gets weaker ratings this week as last week’s B drops to a D. For more information, get Portfolio Grader’s complete analysis of TBRA stock.

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

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

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

Lion Biotechnologies, Inc. (LBIO) is having a tough week. The company’s rating falls from a C to a D. The company also gets F’s in earnings momentum and return on equity. For more information, get Portfolio Grader’s complete analysis of LBIO stock.

This is a rough week for Vitae Pharmaceuticals, Inc. (VTAE). The company’s rating falls to D from the previous week’s C. The company also gets F’s in sales growth, earnings surprise, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of VTAE stock.

This week, Progenics Pharmaceuticals, Inc.’s (PGNX) rating worsens to a D from the company’s C rating a week ago. Progenics Pharmaceuticals, Inc. develops and distributes therapeutic products to treat the unmet medical needs of patients with debilitating conditions and life-threatening diseases. The company also gets F’s in sales growth, operating margin growth, earnings growth, earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of PGNX stock.

ARCA biopharma, Inc.’s (ABIO) rating weakens this week, dropping to a D versus last week’s C. ARCA biopharma, Inc. is a biopharmaceutical company whose main focus is developing genetically-targeted therapies for heart failure and other cardiovascular diseases. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of ABIO stock.

EPIRUS Biopharmaceuticals, Inc. (EPRS) 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 EPRS stock.

Fibrocell Science, Inc. (FCSC) gets weaker ratings this week as last week’s C drops to a D. 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 FCSC stock.

Aptose Biosciences Inc. (APTO) earns a D this week, moving down from last week’s grade of C. 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 APTO stock.

Slipping from a C to a D rating, Rigel Pharmaceuticals, Inc. (RIGL) takes a hit this week. Rigel Pharmaceuticals, Inc. is a clinical-stage drug development company that discovers and develops novel, small-molecule drugs for the treatment of inflammatory and autoimmune diseases, as well as muscle disorders. 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 RIGL stock.

Capricor Therapeutics, Inc. (CAPR) is having a tough week. The company’s rating falls from a D to a F. 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 CAPR stock.

VBI Vaccines Inc (VBIV) experiences a ratings drop this week, going from last week’s C to a D. For more information, get Portfolio Grader’s complete analysis of VBIV stock.

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

This week, ArQule, Inc.’s (ARQL) rating worsens to a D from the company’s B rating a week ago. ArQule, Inc. is a biotechnology company that is engaged in the research and development of cancer therapeutics. The company also gets F’s in earnings revisions, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of ARQL stock.

This is a rough week for Northwest Biotherapeutics, Inc. (NWBO). The company’s rating falls to F from the previous week’s D. Northwest Biotherapeutics, Inc. engages in discovering, developing, and commercializing immunotherapy products to treat cancers in the United States. The company also gets F’s in sales growth and free cash flow. For more information, get Portfolio Grader’s complete analysis of NWBO stock.

This week, Corbus Pharmaceuticals Holdings Inc (CRBP) drops from a C to a D rating. The company also gets F’s in return on equity. For more information, get Portfolio Grader’s complete analysis of CRBP stock.

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

Celsion Corporation’s (CLSN) rating weakens this week, dropping to a F versus last week’s D. Celsion Corporation is an innovative oncology drug development company focused on improving treatment for those suffering with aggressive and difficult to treat forms of cancer. 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 CLSN 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.