The ratings of 26 Biotechnology stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Vertex Pharmaceuticals Incorporated (VRTX) gets weaker ratings this week as last week’s D drops to a F. 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 return on equity. For more information, get Portfolio Grader’s complete analysis of VRTX stock.

This week, Neurocrine Biosciences, Inc. (NBIX) drops from a C to a D rating. Neurocrine Biosciences, Inc. is focused on the discovery and development of therapeutics for neuropsychiatric, neuroinflammatory, and neurodegenerative diseases and disorders. The company also gets F’s in return on equity. For more information, get Portfolio Grader’s complete analysis of NBIX stock.

Alkermes Plc (ALKS) earns a D this week, moving down from last week’s grade of C. Alkermes Plc is a fully integrated biotechnology company committed to developing medicines that will improve patients’ lives. The company also gets F’s in return on equity. For more information, get Portfolio Grader’s complete analysis of ALKS stock.

Slipping from a C to a D rating, Alder Biopharmaceuticals, Inc. (ALDR) takes a hit this week. The company also gets F’s in return on equity. For more information, get Portfolio Grader’s complete analysis of ALDR stock.

La Jolla Pharmaceutical Company (LJPC) 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 LJPC stock.

Eiger BioPharmaceuticals, Inc. (EIGR) slips from a C to a D this week. The company also gets F’s in earnings revisions and earnings surprise. For more information, get Portfolio Grader’s complete analysis of EIGR stock.

This week, Dynavax Technologies Corporation’s (DVAX) rating worsens to a F from the company’s D rating a week ago. Dynavax Technologies Corporation discovers and develops novel products to prevent and treat infectious diseases, asthma and inflammatory and autoimmune 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 DVAX stock.

Advaxis, Inc. (ADXS) declines this week 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 ADXS stock.

Akebia Therapeutics, Inc.’s (AKBA) rating weakens this week, dropping to a D versus last week’s C. The company also gets F’s in earnings revisions, earnings surprise, earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of AKBA stock.

Enzymotec Ltd. (ENZY) is having a tough week. The company’s rating falls from a D to a F. The company also gets F’s in sales growth, earnings growth, earnings surprise, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of ENZY stock.

This is a rough week for Trevena, Inc. (TRVN). The company’s rating falls to D from the previous week’s B. 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 TRVN stock.

TRACON Pharmaceuticals, Inc. (TCON) declines this week from a D 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 TCON stock.

This is a rough week for Ignyta, Inc. (RXDX). The company’s rating falls to F from the previous week’s 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 RXDX stock.

Prana Biotechnology Ltd Sponsored ADR (PRAN) experiences a ratings drop this week, going from last week’s C to a D. Prana Biotechnology Ltd Sponsored ADR is an Australian biotechnology company which researches and develops therapeutic drugs used for treatment of Alzheimer’s Disease and other age-related degenerative disorders such as Parkinson’s Disease and cataracts. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of PRAN stock.

Slipping from a C to a D rating, CareDx, Inc. (CDNA) takes a hit this week. 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 CDNA stock.

This week, VBI Vaccines, Inc.’s (VBIV) rating worsens to a F from the company’s D rating a week ago. 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 VBIV stock.

Calithera Biosciences, Inc. (CALA) 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 CALA stock.

Ohr Pharmaceutical, Inc. (OHRP) earns a D this week, moving down from last week’s grade of C. Ohr Pharmaceutical, Inc. develops pharmaceuticals for wound care and to treat cachexia. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of OHRP stock.

Brainstorm Cell Therapeutics Inc. (BCLI) 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 BCLI stock.

Tenax Therapeutics, Inc. (TENX) gets weaker ratings this week as last week’s D drops 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 TENX stock.

This week, Cytori Therapeutics, Inc. (CYTX) drops from a D to a F rating. Cytori Therapeutics, Inc. develops, manufactures and sells medical products to enable the practice of regenerative medicine. The company also gets F’s in sales growth, earnings growth, earnings surprise, earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of CYTX stock.

Cleveland BioLabs, Inc.’s (CBLI) rating weakens this week, dropping to a F versus last week’s D. Cleveland BioLabs, Inc. is a drug discovery and development company leveraging its proprietary discoveries around programmed cell death to develop treatments for cancer and protection of normal tissues from radiation and other stresses. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of CBLI stock.

AmpliPhi BioSciences Corporation (APHB) is having a tough week. The company’s rating falls from a D to a F. The company also gets F’s in operating margin growth, earnings growth, earnings revisions, earnings surprise, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of APHB stock.

Arena Pharmaceuticals, Inc. (ARNA) experiences a ratings drop this week, going from last week’s D to a F. Arena Pharmaceuticals, Inc. is a clinical-stage biopharmaceutical company that develops innovative therapies offering medical advances and new options for patients. 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 ARNA stock.

This week, Cerulean Pharma, Inc.’s (CERU) rating worsens to a F from the company’s D rating a week ago. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of CERU stock.

Catalyst Pharmaceuticals, Inc. (CPRX) slips from a D to a F this week. Catalyst Pharmaceuticals, Inc. focuses on the development and commercialization of prescription drugs targeting diseases of the central nervous system with a focus on the treatment of drug addiction and epilepsy. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of CPRX 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.