Boryeong to acquire Sanofi's breast cancer drug rights under divestiture condition

Pharmaceutical company Boryeong will acquire the domestic marketing rights to Taxotere, Sanofi's original docetaxel-based anticancer drug used to treat breast cancer — but only on the condition that it divests its own generic, Ditaxel, to a third party to preserve competition in the domestic docetaxel market.

The Korea Fair Trade Commission said Thursday it had reviewed Boryeong's acquisition of Taxotere's marketing rights and determined that the deal posed a significant risk of restricting competition in the domestic docetaxel anticancer drug market, prompting the remedial order.

Under the order, Boryeong must divest all business assets related to Ditaxel to a third party within six months, with a possible extension of up to six additional months if necessary.

Until the divestiture is complete, Boryeong is prohibited from halting Ditaxel's production or supply or from steering customers toward Taxotere. After the sale, Boryeong must supply finished Ditaxel products and provide technology support for a set period if the acquiring company requests it.

The merger was initiated by Boryeong — which sells Ditaxel — to secure global marketing rights to Taxotere, the original drug containing the same active ingredient.

In the domestic docetaxel anticancer drug market, Sanofi holds a 64.7 percent market share, ranking first, while Boryeong ranks second with 13.8 percent. Combined, the two companies account for roughly 78 percent of the market.

The Fair Trade Commission noted that if Boryeong were to directly manufacture and sell Taxotere, applicable regulations would require it to surrender its marketing approval for Ditaxel, reducing the number of competing products available in the market.

The commission also noted that Boryeong had developed South Korea's first alcohol-free docetaxel product in 2023, competing with Taxotere on quality — a competitive dynamic that could weaken after the merger, potentially narrowing consumer choice.

In addition, the commission flagged that Boryeong plans to expand its docetaxel production capacity by roughly 50 times its current level, which could widen the production and sales gap between Boryeong and its competitors.

An economic analysis estimated that the merger would push domestic docetaxel anticancer drug prices up by approximately 4.6 to 9.3 percent and reduce consumer welfare by 3.38 billion won to 7.78 billion won (about $5.13 million).

The Fair Trade Commission accordingly imposed remedial measures — including the asset divestiture and a supply maintenance obligation — to ensure Ditaxel remains an independent competing product after the merger.

"We have put in place detailed remedial measures to ensure that the price and quality competition mechanism between the original drug and the generic is maintained even after the merger," the commission said. "We expect that the direct domestic manufacturing and sale of the original docetaxel anticancer drug will help secure a stable supply base for medicines essential to treating breast cancer and other conditions."