Thread by @JGPharmD

A friend of mine with MS who received rituximab took a 3rd vaccine dose/booster at my urging three weeks ago just had an anti-spike IgG checked that was undetectable. Yes, antibodies aren’t the only part of the immune response, but I am going to use this as an example. 1/

He is a good example of a patient for whom casirivimab-imdevimab is useful for as post-exposure prophylaxis idsociety.org/practice-guide… 2/

The trial that showed benefit to cas-imdev prophylaxis showed a significant benefit in preventing symptomatic Covid-19. The patients who did develop symptoms also recovered more quickly, just as vaccinated patients generally have more mild disease. 3/

These patients were seronegative at baseline, but the trial did not selectively enroll patients unlikely to create their own antibodies- they were relatively healthy pts compared to the EUA recommended population. 4/

Hopefully other therapies will be available also. One of interest is AZD7442, a combination of 2 extended-half-life mAbs against SARS-CoV-2 that was given IM x2 (2 cheeks, I believe) and decreased infections by 72% in a press release. 5/

astrazeneca.com/media-centre/p…

But for now, think of REGEN-CoV for high risk patients who have had Covid19 exposures. Delta is awful, but we have therapeutics now that weren't available during the last surge. Post-exposure prophylaxis is an advance 👍🏻. 6/