What's better than momentum? Mo' momentum.

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

Company

June 22 Weekly Gain My Watchlist
Harvest Natural Resources (NYSE: HNR) $9.12 61% Add
Alexza Pharmaceuticals (Nasdaq: ALXA) $3.97 44% Add
Onyx Pharmaceuticals (Nasdaq: ONXX) $65.67 43% Add
Sun Healthcare (Nasdaq: SUNH) $8.34 31% Add
Oncothyreon (Nasdaq: ONTY) $4.88 24% Add

Source: Barron's.

Harvest Natural Resources was last week's biggest winner, soaring better than 60% after announcing a deal to sell its Venezuelan assets in a $725 million transaction. Harvest expects to pocket roughly $525 million after transaction costs and taxes.

Alexza Pharmaceuticals moved sharply higher after it resubmitted its application for FDA approval on its inhaled antipsychotic drug. Adasuve appears to be an effective treatment, but the stumbling block in the past has been that some patients suffer a decrease in lung function.

Onyx rose after an FDA review panel recommended the company's treatment for relapsed and refractory multiple myeloma.

Sun Healthcare was the picture of health after agreeing to be acquired by Genesis HealthCare at a generous premium. The $275 million deal will cash out Sun investors at $8.50 a share.

Oncothyreon rose after promoting an executive to the role of chief scientific officer. This isn't earth-shaking news, but the biotech had been one of the hardest-hit stocks earlier this year.

More winners for you
It was a great week for these five stocks. If you want to get an early read on some of tomorrow's major gainers, there's a special report on three hidden winners in a booming industry. The report is free -- like this article -- but it won't be around forever, so check it out now.