Updated from 5:06 a.m

RONKONKOMA,, N.Y. ( TheStreet) -- NBTY ( NTY), the nutritional supplements maker, has agreed to be acquired by private-equity firm Carlyle for $55 a share in cash, or $3.8 billion.

NBTY has a market cap of $2.4 billion and annual revenue of about $2.6 billion. The shares closed Wednesday at $37.47.

In a statement Thursday, NBTY said the value of the deal is a premium of about 57% over the stock's average closing price during the 30 trading days to Wednesday.>P/>The news confirms published reports earlier that Carlyle and Blackstone ( BX) were eyeing NBTY.

NBTY sells products under brands Solgar, Rexall and MET-Rx.

-- Reported by Joseph Woelfel in New York.

Get more stock ideas and investing advice on our sister site, Stockpickr.com.

More from Stocks

REPLAY: Jim Cramer on How to Navigate the Stock Market Amid Tariff Worries

REPLAY: Jim Cramer on How to Navigate the Stock Market Amid Tariff Worries

Jim Cramer: 4 Stocks Could Get Throttled By a 'Knock Down Drag Out' With China

Jim Cramer: 4 Stocks Could Get Throttled By a 'Knock Down Drag Out' With China

3 Warren Buffett Stock Picks That Could Be Perfect for Your Retirement Portfolio

3 Warren Buffett Stock Picks That Could Be Perfect for Your Retirement Portfolio

50 Stocks That Could Be Shredded If a U.S. Trade War With China Ignites

50 Stocks That Could Be Shredded If a U.S. Trade War With China Ignites

Why Starbucks Latest Data Reveal Should Worry Investors

Why Starbucks Latest Data Reveal Should Worry Investors