David Livingston, the Dana-Farber/Harvard Med scientist who helped shine a light on some of the key molecular drivers of breast and ovarian cancer, died unexpectedly last Sunday.

One of the senior leaders at Dana-Farber during his nearly half century of work there, Livingston was credited with shedding light on the genes that regulate cell growth, with insights into inherited BRCA1 and BRCA2 mutations that helped lay the scientific foundation for targeted therapies and earlier detection that have transformed the field.

The FDA late Wednesday signed off on authorizing the use of heterologous — or what FDA calls a “mix and match” of a primary vaccine series and different booster doses — for all currently available Covid-19 vaccines, in addition to separately authorizing Moderna and J&J boosters.

On the mix-and-match approach, which FDA officials insisted isn’t too confusing in a press conference, the agency offered the example of an 18-year-old who received the J&J shot at least two months ago and may now receive a single booster of the J&J, a half dose of the Moderna, or the Pfizer-BioNTech booster.

Production problems at a Novavax facility in Maryland have led to delays in the Covax vaccine sharing program. Now, a shortage of 1 billion doses is expected, as the supplier tries to navigate producing a shot up to regulators’ standards, Politico reported Tuesday.

The company has run into trouble with the purity of the vaccine. Novavax has had trouble proving it can produce a shot consistently up to standards, and it has caused significant delays in the rollout to low- and middle-income countries. This follows several delays at Novavax that has put the executive crew on the defensive.

Merck’s molnupiravir may not be officially authorized anywhere in the world yet, but who will get access to it has shaped up to be a huge issue. The Bill & Melinda Gates Foundation is now stepping up to ensure lower-income countries won’t be left behind — and calling on others to follow its lead.

The oral antiviral pill, which was shown to dramatically cut the risk of severe Covid-19 disease and death in a Phase III study, is the latest rallying symbol in the battle against not just the coronavirus but the inequality it’s exposed.

Three Senate Democrats are backing an FDA plan to require mandatory prescriber education for opioids as overdose deaths have risen sharply over the past decade, with almost 97,000 American opioid-related overdose deaths in the past year alone.

While acknowledging a decline in overall opioid analgesic dispensing in recent years, the FDA said it’s reconsidering the need for mandatory prescriber training through a REMS given the current situation with overdoses, and is seeking input on the aspects of the opioid crisis that mandatory training could potentially mitigate.