(Reuters) - AbbVie ( ABBV ) raised its annual profit forecast on Thursday as strong sales of its key immunology drugs, including Humira, helped it beat Wall Street expectations for the second quarter.

Sales of Humira, once the world's top-selling drug, have been declining since its close copies, or biosimilars, hit the U.S. market. There are now 10 Humira biosimilars available in the U.S.

The loss of exclusivity has forced AbbVie ( ABBV ) to reduce the drug's net price to maintain market share, of which it now holds more than 80%.

Humira's global sales fell nearly 30% to $2.81 billion in the second quarter, but beat analysts' estimate of $2.76 billion, according to LSEG data.

AbbVie ( ABBV ) said in February it expects 36% decline in sales for Humira this year in the U.S.

The drugmaker and its investors have focused on sales of newer immunology drugs Skyrizi and Rinvoq to offset the demand erosion for Humira. Skyrizi recorded global sales of $2.73 billion, beating expectations of $2.59 billion, while Rinvoq sales of $1.43 billion topped estimates of $1.36 billion.

AbbVie ( ABBV ) is also facing pressure on its big-selling cancer drug Imbruvica, which was selected as one of the 10 drugs subject to the first-ever price negotiations by U.S. Medicare insurance plans.

For the second quarter, global sales of the oncology drug fell 8% to $833 million, but still beat estimates of $789 million.

Overall, the company's quarterly sales came in at $14.46 billion, beating estimates of $14.03 billion. On an adjusted basis, AbbVie ( ABBV ) earned $2.65 per share, beating estimates by 8 cents.

The company expects its profit to be between $10.71 and $10.91 per share compared to $10.61 to $10.81 earlier.

(Reporting by Puyaan Singh and Leroy Leo in Bengaluru, and Patrick Wingrove in New York; Editing by Arun Koyyur)