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Little has changed in the stock market since we flipped our calendars to 2017, but it's as good a time as any to dig for great investments. If you're looking to inject some fresh ideas into your growth investing strategy, then look no further than Illumina (ILMN 0.43%), Achaogen (NASDAQ: AKAO), and Invitae (NVTA -55.88%).

Undervalued growth giant

DNA sequencing pioneer Illumina has been a perennial growth stock that is trading at a relative discount to its historical prices. A trailing P/E ratio of 55 certainly doesn't appear cheap, and a recent rocketship ride following an onslaught of new business developments unveiled at the J.P. Morgan Healthcare Conference already has the stock off to a 28% gain in 2017. Then again, investors have rarely had the opportunity to buy the stock at a P/E lower than 75. 

ILMN Chart

ILMN data by YCharts.

As the jagged one-year stock chart suggests, however, Illumina and Wall Street have a love-hate relationship of late. Analysts were recently worried that a slipping dependence on lab instruments -- the products most investors think of when they hear the company's name -- and a quarter or two of slow growth hinted at the end of an era that saw the stock deliver 734% gains in the last decade. But not everything is as it seems

The company has always generated most of its revenue and profits from selling reagents and consumables to an installed base of instruments, while services revenue continues to grow at a handsome clip. Add in a flurry of announcements from the industry's flagship conference, including a new sequencing brand and deals with IBM, Phillips, and Bio-Rad, and investors may suddenly want to question whether 10% annual growth is an underestimate.

The path of least resistance

Achaogen has a pretty fun stock chart thanks to a meteoric rise in early December on the heels of positive top-line results for its lead drug candidate, plazomicin. The aminoglycoside is being developed to treat multi-drug-resistant gram-negative infections, and the recent trial proved successful in treating carbapenem-resistant Enterobacteriaceae, or CRE, compared to other commonly used drugs. 

AKAO Chart

AKAO data by YCharts.

Investors are gearing up for a New Drug Application filing with the U.S. Food and Drug Administration in the second half of 2017 and a filing for marketing approval in Europe in 2018. Analysts are predicting peak sales all over the map, ranging from $270 million to over $500 million. Given the increasing rate of antibiotic resistance, specifically CRE, there's reason for optimism at the high end of estimates.

Now comes the hard part: waiting. Management wisely took advantage of the stock's leap to raise $94.5 million in funding, which should allow Achaogen to exit 2016 with over $150 million in cash on hand. But there's not a whole lot left to do outside of regulatory filings that will take all year. All of the company's remaining programs are in preclinical settings, and plazomicin will be its first product on the market. Of course, that means revenue -- composed entirely of grant and contract funding to date -- could see a giant leap in the coming years.

An under-the-radar growth stock

I'm willing to bet that genetic-testing revolutionary Invitae isn't on the radar of many investors. The company is still losing money and generates relatively little revenue, so it isn't likely show up when you screen for traditional growth metrics. Having a market cap of just $370 million and playing in a market currently dominated by Myriad Genetics doesn't help. Oh, and the stock didn't really do anything to catch your attention in 2016, even if a giant leap to start 2017 may have turned some heads.

NVTA Chart

NVTA data by YCharts.

But the stock should definitely be on your radar. Why? The stock has all of the raw potential to be a wish-you-bought-it-earlier growth machine. Invitae has grown at a breakneck pace in recent years as it executes a strategy aimed at upending the genetic testing market. At the end of Q3 2016, billable tests and revenue grew 198% and 186%, respectively, from the year-ago period.

The pace will only accelerate this year and next after management expanded in-network access from 5.5 million individuals at the start of 2016 to over 160 million at the end of the year. Management expects to become cash-flow positive by the end of 2018, which could mean revenue in excess of $100 million. That's quite a jump from trailing 12-month revenue of just $19 million. If the company continues to execute on its vision, then it won't be long before it begins to enter the growth-stock discussion on a frequent basis. 

What does it mean for investors?

Who doesn't like a good growth stock? While Illumina may be on most people's radars, Invitae and Achaogen are likely to be newcomers. Given each company's promising growth prospects in the near future, and relatively low market caps today, 2017 may be the time to start a position.