The sooner, the better.

That's Christophe Weber's time frame for shedding assets as Takeda Pharmaceutical Co. tries to reduce a heavy debt load after completing its $62 billion takeover of Shire PLC. The company has laid out a scenario of a potential $10 billion in divestments in an effort to deleverage.

"It will come as it goes, but we want to move with speed," said the drugmaker's chief executive officer in an interview Tuesday during the JPMorgan Healthcare Conference in San Francisco.

Weber needs to move fast. For one, debt is a huge issue, with net borrowings more than doubling as Takeda takes on about $30 billion in debt to acquire Shire. S&P Global Ratings downgraded Takeda on Tuesday, questioning how quickly it will be able to repair worsening financial ratios.

In addition, Weber needs to whip the new Takeda into shape as competition heats up in the pharmaceutical industry. This year has already seen an explosion of deals, highlighted by Bristol-Myers Squibb Co.'s $74 billion agreement to buy Celgene Corp.

Takeda said it's looking to divest overseas businesses where the company isn't an industry leader and doesn't have critical mass in the market.

"Some of these products are noncore for us, but might be core for others," Weber said.