BOSTON (

TheStreet

) -- Someone forgot to tell investors that the biotech sector goes into slowdown mode during the summer; July was red-hot and August is looking to be just as busy.

The Nasdaq Biotechnology Index was up almost 9% in July, apace with the broader stock market rally.

Human Genome Sciences

( HGSI), boosted by positive phase III lupus drug data, soared almost 400% during the month and the helped the company raise more than $300 million in a greatly over-subscribed follow-on stock offering.

A deluge of media attention and public concern about swine flu pushed a tiny drug stock like

Inovio Pharmaceuticals

(INO) - Get Report

up 161%.

BioCryst Pharmaceuticals

(BCRX) - Get Report

was up 128% in July for the same reasons.

Inside Oculus and BioCryst's Future

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Bristol-Myers Squibb

(BMY) - Get Report

bought

Medarex

( MEDX) for a 90% premium in July, and investors bid up shares of

Acadia Pharmaceuticals

(ACAD) - Get Report

by 86% in anticipation of phase III results from its Parkinson's psychosis drug later this summer.

Even the large-cap biotech stocks had a great month, buoyed by what was generally a strong second-quarter earnings performance.

Celgene

(CELG) - Get Report

was up 19% in July,

Amgen

(AMGN) - Get Report

up 18%, while

Biogen Idec

(BIIB) - Get Report

and

Gilead Sciences

(GILD) - Get Report

managed to eek out smaller 5% gains during the month.

July and August are historically slow months on the biotech calendar. Clearly, the past 30 days broke the rule and August may too, as investors anticipate results of clinical trials and

Food and Drug Administration

approval decisions expected in August and through the fall.

Amgen has a date with an FDA advisory committee on Aug. 13 to discuss and review the company's osteoporosis drug denosumab.

Sequenom

(SQNM)

, the once-highflying genetic test maker taken down by a data-fabrication scandal, may provide an important update during its second-quarter conference call on Aug. 6.

The aforementioned Acadia Pharmaceuticals is expected to release results from a

phase III study of its Parkinson's psychosis drug

pimavanserin before the end of September.

Likewise,

Vivus

(VVUS) - Get Report

and

Arena Pharmaceuticals

(ARNA) - Get Report

will be announcing late-stage results from their respective obesity drugs, while

Poniard Pharmaceuticals

(PARD)

has pivotal data from a phase III study of a small-cell lung cancer drug coming soon.

On the FDA front,

Transcept Pharmaceuticals

(TSPT)

is expecting an approval decision for its insomnia drug on Oct 30.

Auxilium Pharmaceuticals

(AUXL)

has an FDA advisory committee meeting for its drug Xiaflex on Sept. 16 even though the agency's approval decision date for the drug is Aug. 28, a date that is likely to be moved back.

NeurogesX

(NGSX)

should hear from the FDA on its pain drug on Aug. 16. The approval fate of

Spectrum Pharmaceuticals'

(SPPI) - Get Report

cancer drug should be known on Sept. 7.

-- Reported by Adam Feuerstein in Boston

.

Adam Feuerstein writes regularly for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback;

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