Oh, they did? Let's look at how America prevented Africa from manufacturing HIV treatments
"""
In 1997, South Africa tried one tack. It passed a law to allow the
importation of patented medicines that had been produced or sold in another
nation's market with the consent of the patent owner. For example, if the
drug was sold in India, it could be imported into Africa from India. This
is called "parallel importation," and it is generally permitted under
international trade law and is specifically permitted within the European
Union.
However, the United States government opposed the bill. Indeed, more than
opposed. As the International Intellectual Property Association
characterized it, "The U.S. government pressured South Africa ... not to
permit compulsory licensing or parallel imports." 3 Through the Office of
the United States Trade Representative, the government asked South Africa
to change the law — and to add pressure to that request, in 1998, the
USTR listed South Africa for possible trade sanctions.
That same year, more than forty pharmaceutical companies began proceedings
in the South African courts to challenge the government's actions. The
United States was then joined by other governments from the EU. Their
claim, and the claim of the pharmaceutical companies, was that South Africa
was violating its obligations under international law by discriminating
against a particular kind of patent — pharmaceutical patents. The demand
of these governments, with the United States in the lead, was that South
Africa respect these patents as it respects any other patent, regardless of
any effect on the treatment of AIDS within South Africa.
We should place the intervention by the United States in context. No doubt
patents are not the most important reason that Africans don't have access
to drugs. Poverty and the total absence of an effective health care
infrastructure matter more. But whether patents are the most important
reason or not, the price of drugs has an effect on their demand, and
patents affect price. And so, whether massive or mar- ginal, there was an
effect from our government's intervention to stop the flow of medications
into Africa.
By stopping the flow of HIV treatment into Africa, the United States
government was not saving drugs for United States citizens. This is not
like wheat (if they eat it, we can't); instead, the flow that the United
States intervened to stop was, in effect, a flow of knowledge: information
about how to take chemicals that exist within Africa, and turn those
chemicals into drugs that would save 15 to 30 million lives.
"""
https://archive.org/stream/free_culture/freeculture_djvu.txt