The treatment, however, is still in trials; costs a great deal to produce; and involves the use of a fetal cell line derived from an aborted fetus, a practice that the president has repeatedly condemned and his administration has tried to curtail.
Remdesivir, an antiviral drug Mr. Trump also received, was tested using the same cell line. In addition, at least two companies, Moderna and AstraZeneca, are also using that cell line as they race to produce vaccines against the coronavirus, and Johnson & Johnson is testing its vaccine using another cell line originally produced from fetal tissue.
Regeneron’s treatment essentially takes antibodies from Covid-19 survivors and clones them, then administers them to current patients to help their bodies fight off the infection. The fetal cell line, derived from the kidney tissue of a fetus aborted in the 1970s, is used to create virus-like particles as a proxy for live virus, to test the antibodies on.
Mr. Trump’s certainty in the efficacy of the treatment far outstrips that of health experts, who say it is impossible to know whether the antibodies made a difference in his care. In addition, the president is receiving other drugs, including the powerful steroid dexamethasone, which can enhance feelings of well being that in some patients exaggerates into mania.
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The New York Times