6 Biotechnology stocks are moving up in their overall rating this week, according to the Portfolio Grader database. Every one of these is graded an “A” (“strong buy”) or “B” overall (“buy”).

The rating of SAGE Therapeutics, Inc. (SAGE) moves up this week, rising from a C to a B. For more information, get Portfolio Grader’s complete analysis of SAGE stock.

Affimed N.V. (AFMD) gets a higher grade this week, advancing from a C last week to a B. The company also gets A’s in sales growth. For more information, get Portfolio Grader’s complete analysis of AFMD stock.

Amicus Therapeutics, Inc. (FOLD) shows solid improvement this week. The company’s rating rises from a C to a B. Amicus Therapeutics, Inc. is a biopharmaceutical company which is focused on the discovery, development and commercialization of orally-administered, small molecule drugs known as pharmacological chaperones. For more information, get Portfolio Grader’s complete analysis of FOLD stock.

Asterias Biotherapeutics Inc Class A (AST) improves from a C to a B rating this week. The company also gets A’s in sales growth and earnings revisions. For more information, get Portfolio Grader’s complete analysis of AST stock.

Fortress Biotech, Inc. (FBIO) earns a B this week, jumping up from last week’s grade of C. For more information, get Portfolio Grader’s complete analysis of FBIO stock.

ArQule, Inc. (ARQL) boosts its rating from a B to a A this week. ArQule, Inc. is a biotechnology company that is engaged in the research and development of cancer therapeutics. The company also gets A’s in earnings revisions and earnings surprise. For more information, get Portfolio Grader’s complete analysis of ARQL 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.