Takeda Pharmaceutical Co. is nearing the sale of a portfolio of assets in the Middle East, Africa and Russia to separate buyout firms that could help the drugmaker raise about $1 billion to reduce debt, according to people familiar with the matter.

The company is in advanced talks to sell over-the-counter and prescription-drug assets in Russia to Stada Arzneimittel AG, the German pharmaceutical firm owned by Cinven and Bain Capital, the people said, asking not to be identified because the deliberations are private.

It's also close to reaching an agreement to sell its assets in the Middle East and Africa to Acino International AG, a Swiss company owned by Nordic Capital and Avista Capital Partners, they said.

No final decision has been made and talks could still fall apart or face delays, the people said. Representatives for Takeda, Stada, Cinven, Bain, Nordic Capital and Avista declined to comment.

Takeda is also seeking to sell other over-the-counter and prescription-drug businesses in Latin America, Asia and western Europe, Bloomberg News reported last month.

The drugmaker is aiming to raise about $10 billion of disposals, simplifying its portfolio and cutting debt after its $62 billion takeover of Shire PLC. The company is looking to divest noncore businesses outside Japan where the company isn't an industry leader and doesn't have critical mass in the market.