Here's the actual paper
https://www.nejm.org/doi/full/10.1056/NEJMoa2504747
This site has a much better write up than the NYT:
https://innovativegenomics.org/news/first-patient-treated-wi...
Under normal circumstances, developing and testing a new CRISPR therapy takes years, but this patient — and others born every day with severe genetic disorders — do not have years to wait. Getting all of the pieces together for this emergency need took rapid coordination amongst teams at multiple academic and for-profit organizations, only possible because of both years of preparation and some lucky connections.
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Prior to receiving the CRISPR therapy, KJ’s prognosis was poor, but there were several factors that made KJ’s case a good candidate for a rapid CRISPR intervention. An ongoing research study at the IGI called INGENUITI enabled the team to immediately enroll KJ and his parents for genome sequencing and analysis. The mutation in KJ’s genome was a single base — just a one-letter change in his genetic code — and one that could be corrected using base editing, a gene-editing technique that only makes a single-letter edit. Additionally, the researchers needed to edit cells in the liver, where the faulty protein is made. The liver is currently one of the organs in the body that can be targeted for in vivo gene-editing therapies using lipid nanoparticles.
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One of the first steps involved characterizing the mutation in KJ’s genome and designing the guide RNAs that allow the base editor to precisely target a specific letter in the patient’s genome for repair. Kiran Musunuru’s team at Penn accomplished that in record time. Next, the team at the IGI jumped in to do the necessary safety assessment work so that the FDA could assess the risks.