What's better than momentum? Mo'  momentum.

Let's take a closer look at five of this past week's biggest scorchers.

Company

Sep. 21 Weekly Gain My Watchlist
IRIS International (Nasdaq: IRIS) $19.47 45% Add
Acadia Pharmaceuticals (Nasdaq: ACAD) $2.62 24% Add
NII Holdings (Nasdaq: NIHD) $8.34 24% Add
Complete Genomics (Nasdaq: GNOM) $3.09 16% Add
Nanosphere (Nasdaq: NSPH) $3.79 15% Add
Source: Barron's.

IRIS soared last week after receiving a buyout offer. Shareholders of the medical diagnostics provider will be cashed out at $19.50 a share in a tender offer.

Acadia Pharmaceuticals had a strong midweek run. Top-line results for the critical phase 3 study of a promising drug to treat Parkinson's-related psychosis are expected by the end of November. Expect plenty of volatile trading in the coming weeks as the company reaches that important revelation.

NII Holdings made a winning connection after CEO Steve Dussek increased his stake in the company, by 12%. It's a strong show of confidence for the Latin American wireless service provider.

Complete Genomics notched most of last week's gains on Monday, after the gene-sequencing specialist revealed that it would be acquired by China's BGI-Shenzhen. Complete Genomics had put itself up for sale when it initiated a strategic review earlier this year.

Nanosphere gained ground after the TheStreet.com published a bullish article on the provider of advanced molecular diagnostics systems. The shares also got a continued boost on Friday morning after announcing that its CFO would be speaking at an investor conference.

More winners for you
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