By Daniel Clearfield and Peter Murphy (March 21, 2018, 4:37 PM EDT) -- On March 16, 2018, the Pennsylvania Department of Health published new temporary regulations that will expand patient access to pharmaceutical-grade medical cannabis and greatly enhance the commonwealth's nascent medical marijuana program.[1] Successful implementation of Pennsylvania's unique clinical registrant program would put the commonwealth into the vanguard of science-based medical marijuana research and development in the U.S. However, provisions in the new regulations that would prohibit clinical registrant grow/processors from selling their medically based products beyond their own or other clinical registrant dispensaries severely limits the available market for these permittees and threatens the economic viability of the entire program....