(Adds details from conference call; updates share movement)
By Manas Mishra and Aakash B
Feb 6 (Reuters) - Humana Inc's full-year profit forecast came in shy of analysts' estimates on Wednesday as its Medicare Prescription drug plans remained under pressure and said it expects 2019 margins in the fast-growing business to fall short of its own targets.
Shares of Humana were trading down about 2 pct at $296.43 mid-day, reversing course from their premarket gains.
Humana's prescription drug plans have remained under pressure as customers opt for lower priced options from rivals.
"We acknowledge that PDPs (prescription drug plans) have become a commodity, as evidenced by Humana and others having experienced significant declines in PDP enrollment," Chief Executive Officer Bruce Broussard said on a conference call.
Membership in the company's prescription drug plans fell to 5 million in the year ended Dec. 31, versus 5.31 million, a year ago.
While strength in the company's Medicare Advantage (MA)business helped it beat quarterly profit estimates, the company said it expected its 2019 margins in the individual MA business to come in below expectations.
Medicare Advantage, which offers health plans to people 65 and older or those with disabilities, has been growing as the U.S. population ages and as insurers chase the steady government reimbursements for the program.
For the full year 2019, Humana expects adjusted profit of between $17.00 and $17.50 per share, with the midpoint below analysts' estimate of $17.48 per share.
In the fourth quarter, the company beat analysts' estimates for profit and revenue, helped by strength in its business that sells government-backed Medicare Advantage health plans.
The number of people who signed up for the company's Individual Medicare Advantage plans rose to 3.1 million from 2.8 million over the 12 months since December 30, 2018.
Humana said its net income rose to $355 million, or $2.58 per share, in the quarter ended Dec. 31, from $184 million, or $1.29 per share, a year earlier.
Excluding items, the company earned $2.65 per share, beating the average analyst estimate of $2.53 per share, according to IBES data from Refinitiv.
Total revenue rose 7.42 percent to $14.17 billion and beat estimates of $13.98 billion. (Reporting by Aakash Jagadeesh Babu and Manas Mishra in Bengaluru; Editing by Arun Koyyur and Shailesh Kuber)