2014 Change: 62%

Market cap: $4.5 billion

Major holders at Sept. 30: Wellington Management (6.64%), Federated Global Investment Management (5.82%), Vanguard Group (5.70%), T. Rowe Price Associates (5.68%), Gilder Gagnon Howe (5.13%), Fidelity Management and Research (4.63%), Artisan Partners (3.50%), Franklin Advisers (2.89%)

Why is it up? DexCom ($DXCM) has not wasted any time forging ahead with development for its G4 Platinum continuous glucose monitor (CGM). In February, the San Diego, CA-based company scored FDA approval for a pediatric version of the device, making it the first med tech outfit with a CGM approved in the U.S. for toddlers. DexCom notched another win in October, getting a regulatory green light for an add-on to its G4 Platinum device that wirelessly transmits patients' glucose levels through a smartphone using Bluetooth technology. In November, the company chalked up another regulatory nod as the FDA approved a new artificial pancreas algorithm for its CGM device. Investors rewarded DexCom's aggressive growth strategy, sending shares up 6% before the company preannounced its Q4 2014 earnings. DexCom recently reported unaudited product revenues of $257 million, a jaw-dropping 64% increase from the prior year.

What comes next? DexCom laid out big plans for 2015, projecting revenue growth of 35% to 40% in 2015 to reach $340 million to $360 million. The company expanded its patient base in the U.S. by more than 50% last year and plans to increase its sales force by 20% to 25% to grab a bigger market share. In December, Benchmark analyst Jan Wald set the company's price target at $69, forecasting sales growth for the company in 2015. DexCom hopes to carve a bigger niche with new technology and plans to seek FDA approval for a fifth-generation CGM system during the first quarter of 2015, DexCom President and CEO Kevin Sayer said at the JP Morgan Healthcare Conference.

DXCM Chart

DXCM data by YCharts

For more:
DexCom: New CEO reports patient base grew by 50% in 2014
Dexcom snags FDA approval for next-gen artificial pancreas tech for blood glucose monitoring system
FDA approves Dexcom smartphone-enabled device for continuous glucose monitor
FDA cites DexCom for glucose monitoring system medical device reporting violations
DexCom narrows losses as monitoring product revenue soars
FDA: Kids with diabetes can use DexCom's continuous glucose monitor

-- Emily Wasserman (email | Twitter)