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After-hours buzz: PRTK, MRCY, NVCR

Luqman Adeniyi

Check out the companies making headlines after the bell:

Shares of Paratek (NASDAQ: PRTK) skyrocketed 34 percent in extended trading Monday after the company announced positive results in a study for a community-acquired bacterial pneumonia drug. The pharmaceutical company said the second set of Phase 3 Omadacycline results, "will be used to support marketing applications to the United States Food and Drug Administration (FDA) and the European Medicines Agency (EMA)," according to the company's press release. A U.S. New Drug Application is planned for as early as the first quarter of 2018.

Mercury Systems (NASDAQ: MRCY) shares jumped 1 percent after the company announcement will acquire Delta Microwave. The electronic and defense systems company bought Delta Microwave for "$40.5 million in cash, subject to net working capital and net debt adjustments, and is expected to be treated as an asset sale for tax purposes," according to Mercury's press release. Delta creates microwave components that are "an excellent fit for [Mercury Systems] market and content expansion strategy," according to Mercury's president and CEO, Mark Aslett.

Shares of Novocure (NASDAQ: NVCR) are down 2 percent after the company moved 37 percent higher during the trading day . The cancer research and treatment company said it had positive test results for an experimental cancer treatment. During an annual meeting of the American Association for Cancer Research on Sunday, the company said its phase 3 pivotal EF-14 trial showed a consistent and maintained improvement in overall survival at two-to-five year marks.The trial added Novocure's Optune treatment to standard temozolomide chemotherapy to treat newly diagnosed Glioblastoma, a common form of brain cancer.

— CNBC's Mike Juang contributed to this report.