Covid-19 Research Database

The COVID-19 RESEARCH DATABASE is a free resource open to the research and public health community that has been created by Datavant, Inc. and its Research Database partners in an attempt to provide real-world data to individuals conducting non-commercial academic, scientific, and medical research and public health activities concerning COVID-19.

I haven't explored in detail, but it has records from >>100 million patients with respect to claims data, pharmaceuticals, lab reports, and obituaries, and you can log onto the site and they have a system to propose a study.