Equities Research Analysts’ downgrades for Thursday, August 17th:

American Midstream Partners, (NYSE:AMID) was downgraded by analysts at ValuEngine from a hold rating to a sell rating.

Alphatec Holdings (NASDAQ:ATEC) was downgraded by analysts at ValuEngine from a sell rating to a strong sell rating.

Comstock Resources (NYSE:CRK) was downgraded by analysts at ValuEngine from a hold rating to a sell rating.

National Oilwell Varco (NYSE:NOV) was downgraded by analysts at ValuEngine from a hold rating to a sell rating.

News Corporation (NASDAQ:NWS) was downgraded by analysts at BidaskClub from a buy rating to a hold rating.

OneBeacon Insurance Group (NYSE:OB) was downgraded by analysts at BidaskClub from a hold rating to a sell rating.

Petroleo Brasileiro S.A.- Petrobras (NYSE:PBR) was downgraded by analysts at ValuEngine from a buy rating to a hold rating.

PAREXEL International Corporation (NASDAQ:PRXL) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “Parexel International Corporation is one of the largest biopharmaceutical outsourcing organizations in the world, providing a broad range of knowledge-based contract research, medical marketing and consulting services to the worldwide pharmaceutical, biotechnology and medical device industries. With a commitment to providing solutions that expedite time-to-market and peak market penetration, PAREXEL has developed significant expertise in clinical trials management, data management, biostatistical analysis, medical marketing, clinical pharmacology, regulatory and medical consulting, industry training and publishing and other drug development consulting services. Its information technology subsidiary, Perceptive Informatics, Inc., develops and offers a portfolio of innovative technology-based products and services that facilitate clinical drug development and are designed to decrease time to peak sales. “

REGENXBIO (NASDAQ:RGNX) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “REGENXBIO Inc. is a biotechnology company. The Company focuses on the development, commercialization and licensing of recombinant adeno-associated virus gene therapy. Its products candidates include RGX-501, for the treatment of homozygous familial hypercholesterolemia which uses the AAV8 vector to deliver the human low-density lipoprotein receptor gene to liver cells; RGX-111, for the treatment of Mucopolysaccharidosis Type I which uses the AAV9 vector to deliver the human a-l-iduronidase gene to the central nervous system; RGX-121, for the treatment of Mucopolysaccharidosis Type II; RGX-314, for the treatment of wet age-related macular degeneration and RGX-321, for the treatment of X-linked retinitis pigmentosa. REGENXBIO Inc. is headquartered in Rockville, Maryland. “

RE/MAX Holdings (NYSE:RMAX) was downgraded by analysts at BidaskClub from a strong-buy rating to a buy rating.

Unum Group (NYSE:UNM) was downgraded by analysts at BidaskClub from a strong-buy rating to a buy rating.

usell.com (OTCMKTS:USEL) was downgraded by analysts at ValuEngine from a sell rating to a strong sell rating.

UTStarcom Holdings Corp (NASDAQ:UTSI) was downgraded by analysts at ValuEngine from a hold rating to a sell rating.

Nevada Gold & Casinos (NYSEMKT:UWN) was downgraded by analysts at ValuEngine from a buy rating to a hold rating.

Willbros Group (NYSE:WG) was downgraded by analysts at ValuEngine from a hold rating to a sell rating.

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