NEW YORK (Reuters) - Pfizer Inc PFE.N on Tuesday reported lower-than-expected first-quarter revenue as demand for some key drugs and international sales fell short of estimates, sparking a 5.1 percent drop in shares of the largest U.S. drugmaker.

The company, which is exploring a sale of its consumer healthcare business but has seen potential suitors drop out, said it has not received an acceptable offer at this time.

“If we can’t get value, we’ll retain it and invest in it,” Chief Executive Officer Ian Read told analysts. A final decision is still expected this year.

Read, whose previous attempts at huge acquisitions of AstraZeneca AZN.L and Allergan AGN.N were thwarted, said the company does not need a megamerger to drive future growth.

“I don’t see that we need a transformative deal or see one at an appropriate value,” Read said, adding that drugs in development and newer medicines will be able to drive future growth.

He said the company has 15 potential blockbuster medicines in the pipeline that could be launched by 2022.

Pfizer also sees opportunities to significantly expand sales of prostate cancer drug Xtandi for treating less advanced patients, and arthritis drug Xeljanz for ulcerative colitis. U.S. regulatory decisions on the expanded uses are expected later this year.

FILE PHOTO: The Pfizer logo is seen at their world headquarters in New York April 28, 2014. REUTERS/Andrew Kelly/File Photo

Pfizer posted adjusted earnings of 77 cents per share that topped analysts’ average expectations by 4 cents, according to Thomson Reuters I/B/E/S, on lower taxes and cost of goods sold. It did not raise its full-year earnings or revenue forecasts.

Despite strong growth, sales of oral rheumatoid arthritis drug Xeljanz and blockbuster breast cancer treatment Ibrance missed expectations largely due to inventory stocking issues but are likely to rebound, analysts said.

Injected arthritis drug Enbrel was hit by competition from cheaper biosimilars outside the United States. Vaccines and other older drugs, such as Lyrica, Premarin and Celebrex all fell short of analysts’ estimates.

Ibrance sales rose 37.4 percent to $933 million, while analysts looked for $956.6 million. Xeljanz sales totaled $326 million, missing the Wall Street outlook by about $72 million.

Total revenue rose 1 percent to $12.91 billion, while analysts expected $13.13 billion.

SunTrust Robinson Humphrey analyst John Boris said he expected stronger international sales, given favorable foreign exchange rates.

"If you remove the FX tailwind it would have been a much more substantial miss," he said, adding that it was disappointing Pfizer did not raise its 2018 forecasts after rivals, such as Merck & Co MRK.N and AbbVie ABBV.N, raised their outlooks after reporting first-quarter results.

Pfizer still expects adjusted full-year earnings of $2.90 to $3.00 per share on revenue of $53.5 billion to $55.5 billion.

Net profit rose to $3.56 billion, or 59 cents per share, for the quarter, from $3.12 billion, or 51 cents, a year earlier.

Pfizer shares fell $1.87 to $34.74.