PolyMorphine: A Controlled Drug Delivery System for Extended Analgesia

Invention Summary:

Opioid analgesics (e.g., morphine) are widely used for the treatment and management of acute and chronic pain. Morphine has a short half-life with the analgesic effect lasting only 4 to 6 hours. Hence, to maintain the drug at therapeutic levels, bolus doses at fixed intervals (every 4 hours) are administered. Currently available commercial extended-release tablets are successful at maintaining long-term benefits (only up to 24 hours) of morphine without dose escalation.

Scientists at Rutgers have chemically incorporated morphine into a biodegradable poly(anhydride-ester) (PAE) backbone termed PolyMorphine. This polymeric pro-drug aims to alleviate the drawbacks associated with free morphine and the extended-release formulations. PolyMorphine can provide longer duration, sustained morphine release (multi-day) and be readily fabricated into different physical forms (e.g., microspheres) that are not possible with free morphine. Further, the morphine in the polymer cannot be separated by physical means (i.e., crushing the polymer), potentially reducing the occurrence of accidental overdosing.

In vivo studies using mice to determine the analgesic effect provided by PolyMorphine demonstrated extended analgesia due to the multi-day slow release, when compared to free morphine. In addition, preliminary results demonstrate no signs of morphine tolerance development in the animals. In summary, this novel invention has the potential to increase specificity through localized drug release, eliminate requirements for frequent dosing, prevent accidental overdose, and reduce the occurrence of undesired side-effects.

Market Application:

  • Opioids
  • Analgesics
  • Morphine
  • Targeted Drug Delivery
  • Therapeutics
  • Drug Development


Treatment can be targeted via localized drug release, eliminating the requirements for frequent dosing by prolonging the release, and delay the development of opioid tolerance. In addition, this technology will help alleviate misuse and diversion, and help decrease adverse effects.

Intellectual Property & Development Status:

PCT patent pending

Related Publications:

  • Roselin Rosario-Meléndez, Carolyn L. Harris, Roberto Delgado-Rivera, Lei Yu, and Kathryn E. Uhrich. Poly-Morphine: an innovative biodegradable polymer drug for extended pain relief. Manuscript submitted.
  • Carbone, Ashley L. and Uhrich, Kathryn E. 2009. Design and synthesis of fast-degrading poly(anhydride-esters). Macromolecular Rapid Communications 30 (12): 1021-6.
Rutgers ID: 2011-115
Life Sciences
Shan Wan
Senior Licensing Manager
(848) 932-4468
Kathryn Uhrich
Roselin Rosario-Melendez
Drug Delivery
Drug Discovery