Moderna said on Thursday it had paused its plans to build a vaccine manufacturing facility in Kenya, following a post-pandemic decline in demand for Covid-19 vaccines.

The move is in line with Moderna's strategy of resizing its manufacturing network to cut costs, even as it aims to spend around $4.5-billion this year in research and development of several new vaccines, including for cancer and respiratory syncytial virus (RSV).

Many of the messenger RNA (mRNA) vaccines that Moderna is developing, like for HIV and malaria, are at an early stage.

"Given this, and in alignment with our strategic planning, Moderna believes it is prudent to pause its efforts to build an mRNA manufacturing facility in Kenya," the company said.

"This approach will allow Moderna to better align its infrastructure investments with the evolving healthcare needs and vaccine demand in Africa."

The company had said in 2022 that it would invest about $500-million in the Kenyan facility and supply as many as 500-million doses of its mRNA vaccines to Africa each year.

It also had plans to start filling doses of its Covid vaccine in the continent as early as 2023.

However, demand for Covid vaccines has since then waned following the end of the pandemic and Moderna has not received any vaccine orders for Africa since 2022, the company said.

The drugmaker said it had taken more than $1-billion in losses and write-downs related to the cancellation of previous orders from Africa.