BOSTON (

TheStreet

) -- Adam Feuerstein's take on the biotech week that was Oct. 18, 2010:

The weekly shocker: U.S. regulators reject

Amylin Pharmaceuticals'

(AMLN)

diabetes drug Bydureon

.

Not everyone was surprised by the Bydureon decision.

Meet the short-seller who got Amylin right

.

Amylin's Really Bad Day:

Reader Mailbag

.

The week's best-performing stocks in the sector:

Clarient

(CLRT)

(39%),

Verenium

(VRNM)

(21%),

Pharmathene

(PIP)

(21%),

Aryx Therapeutics

(ARYX)

(20%),

Labopharm

(DDS) - Get Report

(15%).

Alexza Pharmaceuticals

(ALXA)

and

Valeant Pharmaceuticals

(VRX)

part ways over the delayed AZ-004.

Generex Biotechnology

(GNBT.PK)

exiled to the pink sheets.

Gilead Sciences

(GILD) - Get Report

earns 90 cents a share (adjusted) in the third quarter on total revenue of $1.94 billion, topping Street consensus.

Genzyme

(GENZ)

forecasts 2011 earnings (adjusted) of $4.30-$4.60 a share, well above Street consensus of $3.85, and says

Sanofi-Aventis

(SNY) - Get Report

is significantly undervaluing the company with its $69-a-share takeover offer. Based on the valuation multiple Sanofi is using today, Genzyme is worth $89 a share, Genzyme said.

Cell Therapeutics

(CTIC) - Get Report

issues press release about European regulatory sign-off on a plan to

study pixantrone in children

, then the company sells preferred shares convertible into 56.8 million common shares and warrants to raise $21 million.

This week's

Biotech Stock Mailbag

:

Titan Pharma

(TTNP.OB)

,

Mela Sciences

(MELA)

,

AVI Biopharma

(AVII)

,

Vanda Pharmaeuticals

(VNDA) - Get Report

and

Savient Pharmaceuticals

(SVNT)

.

Transcept Pharmaceuticals

(TSPT)

releases results from a highway driving study of its Intermezzo sleeping pill, plans to resubmit the drug to the FDA in the first quarter 2011.

The week's worst-performing stocks:

Amylin Pharmaceuticals

(AMLN)

(-46%),

Alkermes

(ALKS) - Get Report

(-25%),

Molecular Insight Pharmaceuticals

(MIPI)

(-22%),

Somaxon Pharmaceuticals

(SOMX)

(-14%),

Senesco Technologies

(SNT)

(-13%).

Cubist Pharmaceuticals

(TSPT)

sells $400 million in convertible debt.

A

paragraph IV generic challenge was filed against Silenor

, the sleeping pill recently launched by

Somaxon Pharmaceuticals

(SOMX)

.

Alexion Pharmaceutials

(ALXN) - Get Report

announces positive, interim results from a pivotal study of Soliris in patients with atypical Hemolytic Uremic Syndrome. The company also reports third-quarter earnings of 50 cents a share on revenue of $141.6 million, topping Street consensus.

--Written by Adam Feuerstein in Boston.

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.

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.

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.

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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