It's been a good last few weeks for makers of cancer-fighting vaccines. On Wednesday, Pfizer (NYSE: PFE) and small biopharma Avant Immunotherapeutics (Nasdaq: AVAN) signed a partnership deal worth as much as $440 million for CDX-110, Avant's immunotherapy candidate.

The deal with Avant gives Pfizer the worldwide marketing rights for $40 million in up-front cash, $390 million in potential milestone payments, and a double-digit royalty on sales of the vaccine if it's approved for marketing. Avant has its hand in a host of vaccines in development, and the deal with Pfizer for CDX-110 is only one of several it has made with other large-cap pharmaceuticals and other companies for its vaccines.

CDX-110 is in phase 2 or 3 testing to treat glioblastoma multiforme. In a 375-person clinical study, the company is looking at CDX-110 in combination with radiation and a commonly used chemotherapy. Avant is hoping to show that CDX-110 extends a patient's progression-free survival  and overall survival more than radiation and chemotherapy alone. The trial should wrap up late next year.

Any investors who believe that a rising tide lifts all boats must recognize that the cancer immunotherapy space is a good place to be. Three weeks ago, Cell Genesys (Nasdaq: CEGE) signed a deal for its GVAX prostate-cancer immunotherapy candidate with Takeda; last week, Antigenics' (Nasdaq: AGEN) kidney vaccine was approved for marketing in Russia. Now, this move by Avant further bolsters the cancer-vaccine part of the biopharma sector.

The success or failure of cancer vaccines like these and Dendreon's (Nasdaq: DNDN) Provenge will be determined in the clinic, and we'll see whether they can get approved in more developed pharmaceutical markets like the U.S., Japan, or the European Union. But any good news is certainly welcome in a sector that has struggled in recent years.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. Pfizer is a pick of both the Income Investor and the Inside Value newsletters. The Fool has an A+ disclosure policy.