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African trial denied access to Paxlovid
Public-health advocates are dismayed that Pfizer has denied a request by researchers to include its COVID-19 drug, Paxlovid, in a pivotal African clinical trial. The move hinders efforts to test the treatment in African populations and in combination with therapies that could potentially expand its utility on the continent. Pfizer says it can make up to 120 million courses of the treatment by the end of the year, of which 4 million will go to the United Nations children’s charity UNICEF. “We’re focusing our efforts and resources in a way that maximizes availability of our overall supply,” said Pfizer in a statement.
Leading COVID scientists face abuse
Two surveys suggest a dispiriting, if unsurprising, trend: COVID-19 researchers with higher profiles are more likely to be harassed. In March, Science reported that 38% of researchers who have published multiple papers on COVID-19 said they had experienced at least one type of harassment, such as personal insults or death threats, related to their work on the disease. The results have parallels with the findings of a Nature survey, published in October. In this survey, 81% of respondents said that they had experienced personal attacks or trolling — even if only rarely — after talking to the media about COVID-19. “You just get overwhelmed by the hate,” says epidemiologist Tara Smith.
CRISPR-baby creator out of jail
He Jiankui has been released from prison in China. The biophysicist shocked the world in 2018 by announcing that he had used the CRISPR genome-editing technique to alter embryos that were implanted and led to the birth of two children. “It is extraordinary and unusual that [He Jiankui] and some of his colleagues were imprisoned for this experiment,” says anthropologist Eben Kirksey, who has written about He’s controversial work. “At the same time many of [his] international collaborators — like Michael Deem and John Zhang — were never sanctioned or formally censured for involvement.”
MIT Technology Review | 5 min read
Read more: How to protect the first ‘CRISPR babies’ (Nature | 6 min read, from February)
Features & opinion
Models could fine-tune vaccine doses
Mathematical and computational models might be able to aid scientists in deciding the best dose for a future COVID-19 vaccine. The spectacular speed and effectiveness of the vaccines rolled out so far could have been even better if the amount given in each shot had been based on more than educated guesses, say advocates of the new technologies. Researchers typically use past experience and animal testing to find a sweet spot for vaccine doses that minimizes side effects and maximizes efficacy. Modelling that considers side effects, efficacy, the interval between doses and the type of immune response might be able to help.

Source: Adapted from ref. 6
How to tame the crypto chaos
To avert privacy breaches, scams and environmental damage, governments and central banks need to know how best to regulate crypto and digital currencies, argue finance researchers Andrew Urquhart and Brian Lucey. They set out nine research priorities to address legality, scalability, usability and acceptability on this financial frontier.
Let Ukrainian refugee response inspire you
The response to the needs of people fleeing Ukraine shows the way all refugees should be treated, argues political philosopher Serena Parekh: with dignity. “What was unthinkable two months ago — that Europe could feed, house and economically integrate a huge number of refugees quickly and with little animosity — has become a reality,” she writes. “The response — compassion, solidarity and bureaucratic efficiency — should serve as a model for how the world accommodates all refugees.”