FLINT, Mich. — Diplomat Pharmacy Inc. has begun a follow-on public offering of 7.4 million shares of its common stock.

The independent specialty pharmacy said late Monday that it’s selling 4.4 million shares of common stock, and certain shareholders are selling 3 million shares of common stock. In addition, the company and selling shareholders aim to grant the underwriters a 30-day option to buy up to an aggregate of another 1.11 million shares.

Diplomat plans to raise about $88 million of gross primary proceeds to be used for debt repayment, under an amended line of credit after the expected near-term closing of the BioRx LLC acquisition, as well as for working capital and other general corporate purposes, which may include further debt repayment or future acquisitions.

The company added that the selling shareholders and certain option holders will receive the remaining $118 million of proceeds expected to be raised in the offering.

Diplomat had filed for the follow-on stock offering with the Securities and Exchange Commission last week, saying that the offering could raise about $200 million, depending on market conditions. The company announced the deal to acquire BioRx, a pharmacy and infusion services company, in late February.

Last October, Diplomat raised about $145 million in an initial public offering of about 15 million shares on the New York Stock Exchange.