In the first stage of the transaction, Sopharma will take over 25% of Pharmanova's equity capital, the Bulgarian company said in a stock exchange filing on Tuesday.
Sopharma agreed in July to acquire all of Pharmanova's shares within two years for an undisclosed amount, with 50% of the target company to be purchased next year.
Pharmanova manufactures generic and over-the-counter drugs, dietary supplements, ointments and medical devices for the markets of Serbia, Bosnia and Herzegovina, Montenegro and North Macedonia.
Last month, Sopharma posted a 62% annual jump in net profit to 38.4 million levs ($20.9 million/19.6 million euro) in the January-September period, mostly driven by exports.
As at 1133 CET on Wednesday, shares in Sopharma traded 0.55% lower at 7.20 levs on the Sofia bourse.
(1 euro = 1.95583 levs)