Eli Lilly agreed to pay up to $47.5 million up front for Centrexion’s chronic pain treatment currently in Phase I trials.

The deal could be worth up to $575 million if Centrexion’s CNTX-0290 hits its development and regulatory milestones and another $375 million if the drug is approved and reaches certain sales milestones.

CNTX-0290 is a small molecule somatostatin receptor type 4 agonist developed to treat chronic pain—and most important, isn’t an opioid and isn’t addictive.