Wednesday was a relatively calm day for the stock market, with major benchmarks generally posting modest gains to move incrementally further into record territory. Investors continued to debate the market's overall valuation, with some pointing to indicators like the cyclically adjusted price-to-earnings ratio as justifying concern, while others point to low interest rates as a way of explaining high earnings multiples. Meanwhile, some individual companies had good news that sent their shares much higher. MannKind (NASDAQ: MNKD), Intelsat (OTC:INTE.Q), and Benefitfocus (NASDAQ:BNFT) were among the best performers on the day. Below, we'll look more closely at these stocks to tell you why they did so well.

MannKind keeps rising

Shares of MannKind jumped 25.5%, extending their gains during the first three trading sessions in October to more than 60%. On Monday, the biotechnology company said that the U.S. Food and Drug Administration had approved label changes to MannKind's inhalable insulin product Afrezza, which it hopes will allow its sales efforts to build momentum going forward. MannKind also said that it had successfully exchanged new common stock for outstanding warrants issued last year, cleaning up the company's capital structure and giving it more flexibility for future financial moves. Investors are excited about MannKind, and that's showing in its rapidly rising share price.

13 different models of inhalers offered by MannKind.

Image source: MannKind.

Intelsat gains altitude

Intelsat stock climbed more than 16.5%, following a double-digit percentage gain on Tuesday. The satellite communications provider initially jumped on reports that the company would seek to have the Federal Communications Commission allow land-based mobile providers to collaborate with satellite service providers to offer 5G service in the midband spectrum that Intelsat and its peers use extensively. With investors already having had high hopes for Intelsat, the latest news seems like a natural progression that could result in new sources of revenue for the company if the initiative gains FCC approval.

Benefitfocus gets healthier

Finally, shares of Benefitfocus gained 6%. The cloud-based benefits management software specialist said today that it had released a new solution to help employer clients keep track of consumer-directed healthcare accounts like health savings accounts. With the platform, clients can help their employees enroll in HSAs and similar programs seamlessly, and handling reimbursements for eligible expenses is possible via mobile device submissions. The package also handles COBRA continuation coverage after an employee ends employment, creating further efficiencies. The cloud computing revolution has been extremely promising for many companies, and Benefitfocus has worked particularly hard to make its offerings attractive to its customers.

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