Humana Inc. says it may earn less than it had hoped this year, mainly because claims at the company’s Medicare prescription drug plan are running higher than expected.

Humana, Louisville, Ky., says the PDP claims increase could cut first-quarter profits to about 40 cents per share, from an earlier estimate of about 80 cents per share.

WellPoint Inc., Indianapolis, warned Monday that its first-quarter profits might fall to about $1.16 to $1.26 per share, from a prior forecast of $1.44 per share.

WellPoint said it was cutting its earning estimates partly because claims costs are up and partly because a weaker economy seems to be affecting individual and small group plan enrollment.