Oral opioid-induced constipation drugs present big opportunity for AstraZeneca

September 23, 2009 – 2:11 pm by Colette Pilkus

Earlier this week, AstraZeneca and Nektar Therapeutics signed a worldwide agreement for two development programs to address opioid-induced constipation for $125 million. NKTR-118 has completed a Phase II clinical trial and is being developed to treat constipation caused by the use of opioid pain products. NKTR-119, in preclinical development is intended to combine oral NKTR-118 with selected opioids, with the goal of treating pain without the side effect of constipation traditionally associated with opioid therapy. AstraZeneca will continue the development of this program, including determining the appropriate opioid combinations with NKTR-118. AstraZeneca expects completion of the design of the Phase III program in the near future, and anticipates filing the drug with regulators in 2013.

NKTR-118 and NKTR-119 are both oral medications. Since no oral drugs have been approved in the United States that are indicated to treat opioid-induced constipation, AstraZeneca has a lot to gain from the deal.

According to IMS Health, about 230 million prescriptions were written for opioids in 2007 in just the United States, which is estimated to represent about 65% to 75% of the worldwide opioid market. It is also estimated that for those patients who take opiates chronically for pain management, anywhere from 40% to 90% of such patients will develop constipation. Less than half of those patients find effective relief from current treatment options that include prescription and over-the-counter laxatives and stool softeners.

The only FDA approved drug for opioid-induced constipation is Relistor, marketed by Wyeth. The drug is only available as a subcutaneous injection. Relistor for oral administration is being studied in Phase II trials.

If AstraZeneca and Nektar seek an approval for these products in Europe, however, the drug will compete with another oral medication: Mundipharma International Ltd.’s Targin. Targin is a prolonged release oral combination of oxycodone and naloxone for severe pain and the side effect of opiod induced constipation. Targin has been marketed in Germany since October 2006 and has recently been approved in several other European countries.

“AstraZeneca has long-term experience in both neuroscience and gastrointestinal areas of medicine,” says Emily Denney, senior director, brand corporate affairs, AstraZeneca. “In addition, we have a strong heritage in oncology. Given 40% to 45% of cancer patients on opioids have OBD, this heritage also plays a role. So, we believe that both of these news investigational programs will fit nicely into the overall AstraZeneca portfolio.”

AstraZeneca stood out as the ideal development and commercialization partner for NKTR-118 and NKTR-119, according to a Nektar spokesperson. Nektar executives believe that AstraZeneca has a tremendous and proven reputation for creating and establishing market-leading brands. From an R&D vantage point, Nektar’s programs fit well in three areas where AstraZeneca has deep clinical development, regulatory knowledge, and expertise. Nektar believes that this expertise will be important in helping to realize the potential of NKTR-118 and NKTR-119 to help patients.

“Combined with their strong global sales forces in primary care and specialty areas, we know that our programs could achieve broad and deep market penetration,” Nektar’s spokesperson told R&D Directions.

Tags: AstraZeneca, Nektar, NKTR-118, NKTR-119, Relistor, Targin