Development and Evaluation of a Methadone Protocol for Severe Chronic Pain Management

Condition(s) targeted: Pain, Chronic

Intervention: Methadone (Drug)

Phase: Phase 4

Status: Completed

Sponsored by: Mahidol University

Official(s) and/or principal investigator(s):
Chuthamanee Suthisisang, Ph.D., Study Chair, Affiliation: Thailand: Faculty of Pharmacy, Mahidol University
Phutsadee Pudchakan, Bsc.Pharm, Principal Investigator, Affiliation: Thailand: Faculty of Pharmacy, Mahidol University
Krittika Tanyasaensook, Ph.D., Study Director, Affiliation: Thailand: Faculty of Pharmacy, Mahidol University
Pongparadee Chaudakshetrin, M.D., Study Director, Affiliation: Thailand: Faculty of Medicine Siriraj Hospital

Methadone is a synthetic mu opioid agonist that has been proved as clinically effective in pain management. However, methadone usage for pain control in Thailand has been limited because physicians are not familiar with its dosing and concern about the risk of drug accumulation and cardiac arrhythmia. Therefore, this prospective study was conducted to evaluate the efficacy and safety of a methadone protocol in Thai patients with severe chronic noncancer and cancer pain.

Official title: Development and Evaluation of a Methadone Protocol for Severe Chronic Pain Management

Study design: Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment

Primary outcome: Pain score

Secondary outcome:

pain interferences scores

severity of adverse effects

QTc intervals

Neuropathic pain score

Detailed description: Chronic pain is defined as pain that persists beyond normal tissue healing time, which is assumed for 3 months by the IASP. The symptoms include either continuous or intermittent pain, that could be caused by tumor or other multiple etiologies. The consequence of uncontrolled chronic pain presents not only physiologic symptoms but also psychiatric disorders leading to severely impact daily living. In Thailand, the use of methadone for pain management has been limited because physicians are not familiar with its dosing and concern about the risk of drug accumulation and cardiac arrhythmia. Therefore, the aim of this study is to evaluate the efficacy and safety of a protocol of methadone dosing in outpatients with severe chronic pain. Thirty four chronic pain patients will be included to initiate methadone use following the protocol. Pain scores, pain interferences scores, neuropathic pain score, severity of adverse effects, and QTc intervals will be assessed at baseline, and two, four, eight, and twelve weeks after starting methadone. The approved protocol of methadone therapy obtained from this study could be clinically utilized by physicians for severe chronic pain management.

Minimum age: 18 Years. Maximum age: N/A. Gender(s): Both.

Criteria:

Inclusion Criteria:

- Outpatients aged 18 or over who suffered from severe chronic cancer or noncancer pain

to be firstly treated with methadone as analgesics Exclusion Criteria:

- QTc interval that was more than 500 msec

- History of opioid addiction

- Having structural heart diseases

- During pregnancy or lactation period

- Patients who have hypersensitivity to methadone

Siriraj Hospital, Bangkoknoi, Bangkok 10700, Thailand

Related publications:

Mercadante S, Casuccio A, Calderone L. Rapid switching from morphine to methadone in cancer patients with poor response to morphine. J Clin Oncol. 1999 Oct;17(10):3307-12.

Mercadante S, Casuccio A, Fulfaro F, Groff L, Boffi R, Villari P, Gebbia V, Ripamonti C. Switching from morphine to methadone to improve analgesia and tolerability in cancer patients: a prospective study. J Clin Oncol. 2001 Jun 1;19(11):2898-904.

Ripamonti C, Groff L, Brunelli C, Polastri D, Stavrakis A, De Conno F. Switching from morphine to oral methadone in treating cancer pain: what is the equianalgesic dose ratio? J Clin Oncol. 1998 Oct;16(10):3216-21.

Bruera E, Sweeney C. Methadone use in cancer patients with pain: a review. J Palliat Med. 2002 Feb;5(1):127-38. Review.

Pearson EC, Woosley RL. QT prolongation and torsades de pointes among methadone users: reports to the FDA spontaneous reporting system. Pharmacoepidemiol Drug Saf. 2005 Nov;14(11):747-53.

Starting date: July 2011
Last updated: January 7, 2015