COVID-19 Open Research Dataset (CORD-19), "a free resource of over 45,000 scholarly articles, including over 33,000 with full text, about COVID-19 and the coronavirus family of viruses for use by the global research community." Search the dataset using CORD-19 Explorer. The content is from PubMed Central, the World Health Organization, bioRxiv, and medRxiv. The resource is sponsored by the Allen Institute for AI and partners.
NIH's COVID-19 Topic Page is a portal to COVID-19 research, news, visualizations, and funding opportunities.
Sage Journals has opened access to all COVID-19 research articles in their collection, including the disciplines of medicine, public health, and social sciences.
Springer Nature is providing free access to their journals, commentary, and books related to COVID-19.