Practical Guide for Using Methadone in Pain and Palliative Care Practice

Methadone for Cancer Pain Management in Children: A Review of Literature

Pain associated with cancer is a common feature among children and adolescents. Among opioids, methadone is a unique drug for its multiple mechanisms of action. Methadone is currently underutilized in children. The use of methadone for cancer pain management in children was assessed in a systematic review. Altogether, 141 children receiving methadone were examined, and another 126 children were assessed for QT prolongation. In the clinical studies, modalities of use, dosing, and duration of assessment were highly variable. In general, methadone was effective and well tolerated with a limited tendency for dose increases. QT prolongation was reported in a percentage of patients independently of the dosages or other variables. The majority of studies considered the use of methadone to be safe and effective in children. Despite methadone possessing interesting properties that make this drug unique in a pediatric context, data is limited, and the literature available is based on retrospective studies. Methadone could be an effective, inexpensive, and versatile medication in children with cancer who have pain. This drug deserves more interest and should prompt studies of better quality with a larger number of patients.

Network-based drug repurposing for HPV-associated cervical cancer

In women, cervical cancer (CC) is the fourth most common cancer around the world with average cases of 604,000 and 342,000 deaths per year. Approximately 50% of high-grade CC are attributed to human papillomavirus (HPV) types 16 and 18. Chances of CC in HPV-positive patients are 6 times more than HPV-negative patients which demands timely and effective treatment. Repurposing of drugs is considered a viable approach to drug discovery which makes use of existing drugs, thus potentially reducing the time and costs associated with de-novo drug discovery. In this study, we present an integrative drug repurposing framework based on a systems biology-enabled network medicine platform. First, we built an HPV-induced CC protein interaction network named HPV2C following the CC signatures defined by the omics dataset, obtained from GEO database. Second, the drug target interaction (DTI) data obtained from DrugBank, and related databases was used to model the DTI network followed by drug target network proximity analysis of HPV-host associated key targets and DTIs in the human protein interactome. This analysis identified 142 potential anti-HPV repurposable drugs to target HPV induced CC pathways. Third, as per the literature survey 51 of the predicted drugs are already used for CC and 33 of the remaining drugs have anti-viral activity. Gene set enrichment analysis of potential drugs in drug-gene signatures and in HPV-induced CC-specific transcriptomic data in human cell lines additionally validated the predictions. Finally, 13 drug combinations were found using a network based on overlapping exposure. To summarize, the study provides effective network-based technique to quickly identify suitable repurposable drugs and drug combinations that target HPV-associated CC.

Oral Methadone versus Morphine IR for Patients with Cervical Cancer and Neuropathic Pain: A Prospective Randomised Controlled Trial

Objectives

In India, cervical cancer is the most common cancer among women and makes up for up to 29% of all registered cancer in females. Cancer-related pain is one of the major distressing symptoms for all cancer patients. Pain is characterised as somatic or neuropathic, and the total pain experience is often mixed. Conventional opioids are the backbone of analgesic treatment but are most often not sufficient in alleviating neuropathic pain, common in cervical cancer. Accumulating evidence of the advantage of methadone compared to conventional opioids, due to agonist action at both μ and q opioid receptors, N-methyl-D-aspartate (NMDA) antagonist activity and the ability to inhibit the reuptake of monoamines has been demonstrated. We hypothesised that, with these properties', methadone might be a good option for the treatment of neuropathic pain in patients with cervical cancer.

Material and Methods

Patients with cervical cancer stages ll-lll were enrolled in this randomized controlled trial. A comparison was made between methadone versus immediate release morphine (IR morphine), with increasing doses until pain was controlled. Inclusion-period was from October 3rd to December 31st 2020, and the total patient-study period was 12 weeks. Pain intensity was assessed according to the Numeric Rating Scale (NRS) and Douleur Neuropathique (DN4). The primary objective was to determine whether methadone was clinically superior versus noninferior to morphine as an analgesic for the treatment of cancer related neuropathic pain in women with cervical cancer.

Results

A total of 85 women were included; five withdrew and six died during the study period, leaving 74 patients completing the study. All participants showed a reduction in mean values of NRS and DN4 from the time of inclusion and to the end of the study period, for IR morphine and methadone 8.4-2.7 and 8.6-1.5, respectively (P < 0.001). The DN4 score mean reduction for Morphine and Methadone were 6.12-1.37 and 6.05-0, respectively (P < 0.001). Side effects were more common in the group of patients receiving IR morphine compared to the patients treated with methadone.

Conclusion

We found that Methadone had a superior analgesic effect with good overall tolerability compared with morphine as a first-line strong opioid for the management of cancer-related neuropathic pain.

Treatment of painful calciphylaxis with methadone in a palliative care unit: A case report

A 72-year-old female was admitted with severe calciphylaxis-associated bilateral leg pain on a background of end-stage renal failure on hemodialysis. Palliative care input was requested, and following transfer to our unit she was commenced on low-dose methadone as adjunctive analgesic therapy. A remarkable and sustained analgesic response was observed. Calciphylaxis is associated with severe pain, and careful consideration of analgesic agents and their pharmacokinetics in patients with end-stage renal failure is required.

The Introduction and Experiences of Methadone for Treatment of Cancer Pain at a Low-resource Governmental Cancer Center in India

Objectives

This study aimed to describe the clinical experience of the health-care professionals (HCPs) responsible for the introduction of methadone, for the treatment of complex cancer pain, at a low-resource hospital in India in a patient-group, burdened by illiteracy, and low socio-economic status.

Materials and Methods

Ten HCPs: Four medical doctors, four nurses, one pharmacist, and one hospital administrator were interviewed. The interviews are examined using a qualitative conventional content analysis.

Results

The interviews showed a confidence amongst the HCPs, responsible for the safe introduction of methadone in a stressful and low-resource surrounding, to patients with cancer pain and the different aspects of methadone, as initiation, titration, and maintenance of treatment.

Conclusion

Introduction of methadone for cancer pain management is safe and feasible although low resources in a challenging hospital setting and care environment.

First-line methadone for cancer pain: titration time analysis

BACKGROUND

Methadone is a low-cost, strong opioid that is increasingly used as a first-line treatment for pain in palliative care (PC). Its long and unpredictable half-life and slow elimination phase can make titration challenging. Evidence for titration modalities is scarce.

OBJECTIVE

To describe the titration phase of the treatment with low-dose first-line methadone and the use of methadone for breakthrough pain.

METHODS

Prospective study with strong opioid-naïve patients with moderate to severe cancer pain followed at a tertiary PC unit in Argentina. Starting methadone dose was 2.5-5 mg/day every 8, 12, or 24 h. Titration allowed daily dose increases from day 1, and prescription of oral methadone 2.5 mg every 2 h with a maximum of 3 rescue doses/day for breakthrough pain. Pain control, methadone stabilization dose, and adverse effects, among other variables, were daily assessed over the first 7 days (T0-T7).

RESULTS

Sixty-two patients were included. Initial median (IQR) methadone dose was 5 (2.5) mg/day. Pain intensity decreased from a median (IQR) of 8 (2.3) at T0 to 4 (2.3) at T1 and remained ≤ 4 until T7 (all p < 0.0001 compared to T0). Similar results were obtained through the categorical and tolerability scales for pain. Fifty patients (81%) reached pain control, 66% in the first 48 h. Methadone daily doses at T2 and T7 were higher than that at T0: 7.5 (3) and 6.7 (5.5) versus 5 (2.5), respectively (all p < 0.05). The opioid escalation index at T7 was 1.7%. The median (IQR) number of rescues, stabilization dose, and time for stabilization was 0 (1), 5(4.5) mg, and 3(2) days, respectively. Two patients were discontinued due to delirium. All other side effects were mild.

CONCLUSIONS

First-line, low-dose methadone using rescue methadone resulted in a pronounced and rapid decrease in pain, with minimal need for titration and for breakthrough doses, and no evidence of accumulation or sedation by the end of the week.

The Use of Methadone in Adult Patients with Cancer Pain at a Governmental Cancer Center in India

Background:

Management of cancer-related pain relies on the access to opioids. When regular opioids as morphine are not tolerated or are insufficient, adjuvant opioids as methadone are an affordable and effective analgesic.

Aim:

The aim of the project was to describe the pattern of use and clinical experiences of methadone in patients with cancer-related pain at a low-resource hospital in Hyderabad, one of few Indian cancer centers with permission to prescribe methadone.

Methods:

Medical records of all patients who had been prescribed methadone, September 9, 2017 and November 19, 2019 were studied retrospectively. Data on analgesic treatment and opioid side effects were analyzed.

Results:

A total of 93 adult cancer patients were included in the study. A majority of patients (79%) were prescribed opioid analgesic, mainly morphine, before methadone introduction. The initial daily dose of methadone ranged between 5 and 22.5 years and in the vast majority of the patients 5 mg, divided in two daily administrations. A good analgesic effect, with decreased pain, was reported in 60% of the patients. No severe side effects were reported.

Conclusions:

In this study, methadone as a primary opioid was used with a good analgesic effect for cancer pain in a low-resource setting. Indication for methadone was mainly uncontrolled pain with a regular opioid treatment. No severe adverse effects were reported. Further research and prospective studies are needed on methadone treatment in low-resource settings to establish the robust guidelines to support prescribing physicians.

The Use of Methadone in Pediatric Cancer Pain - A Retrospective Study from a Governmental Cancer Center in India

Background:

The management of cancer-related pain relies on access to opioids. When regular opioids are not tolerated, or are insufficient, methadone is an affordable and effective analgesic.

Aim:

The aim of the project was to describe the pattern of use and clinical experience of methadone in pediatric cancer pain at a governmental cancer hospital in Hyderabad, one of the four Indian cancer centers with permission to prescribe methadone.

Methods:

This was a retrospective study of medical records of all children, under the age of 18, who had been prescribed methadone from September 9, 2017, to November 19, 2019. Data on analgesic effect, prior and concomitant analgesic treatment, opioid side effects, and the handling of methadone were analyzed.

Results:

A total of 11 children were identified and studied. Methadone was introduced mainly when pain was uncontrolled by regular opioids. Initial daily doses ranged from 1 to 15 mg. The duration of treatment ranged from 7 to 307, with a median of 50 days in the nine patients where treatment exceeded one single dosage. Good analgesic effect was reported in 5/9 children, unchanged from previous analgesic treatment in three patients and without any effect in one child. No severe side effects were reported.

Conclusion:

Low-dose methadone in the treatment of pediatric cancer pain at a low-resource cancer center was safe and well tolerated by the patients, with long treatment durations. It was safely managed, administered with single to double daily dosages, hence easy for patients and family to handle, and an affordable treatment option.

Methadone in Cancer Pain

Methadone has been an unique, versatile, cost effective, synthetic opioid utilized in nociceptive as well as neuropathic pain. Pain and palliative care physicians started accepting methadone in treatment of complex pain associated with advanced cancer and neuropathic pain syndromes in which conventional opioids were no longer effective. The challenge is in accepting methadone as a main stream first line opioid, from being considered as a second line replacement/substitution drug all these years. Methadone has a significant role as opioid rotation in refractory cancer pain, especially when started early leading to successful conversion. Advantages of methadone in paediatric patients with advanced cancer were its safety and efficacy as a first-choice opioid, availability as a liquid formulation and its infrequent dose requirements. Methadone is neither recommended nor justified to be used as an anti-cancer drug and its role as an anti-cancer agent is a misconception. Many guidelines were proposed after 2008 to address methadone safety. Most of them emphasized on prevention of cardiac arrhythmia and association of methadone with QTc prolongation rather than address the real issue. Methadone has been established to be safe when used in opioid naïve patients with careful titration instituted in an ambulatory setting and has equal success in opioid rotation in outpatient setup. Methadone prescription should be carried out by experienced pain and palliative care providers with careful dose titration and clinical monitoring.

Breaking the barrier: Challenges of methadone use – An introductory observation

Background:

Palliative care physicians in India have achieved access to methadone for pain relief in cancer patients. Despite being an effective drug in terms of analgesia, there are a number of reasons why this opioid medication is not as much as popular as morphine. We identified and tried to overcome a few such barriers in treating cancer pain with methadone.

Methods:

The clinical information of ten adult cancer patients (six males and four females), who voluntarily received methadone for their severe pain in the month of August 2019 were analysed retrospectively. We converted morphine to methadone in all ten patients under the supervision of an experienced practitioner.

Results:

During the methadone therapy, eight out of ten patients who were given methadone exclusively for their pain had adequate pain relief initially. The barriers identified included difficult titration methods due to distinct pharmacology, patient selection, clinical inertia, communication and co-ordination among physicians, communication among patient and physician, and patient and caregivers, and vigilant monitoring.

Conclusion:

Methadone is still finding its place in India for cancer pain management. As the drug is new to Indian practitioners, we have to overcome these barriers and facilitate its judicious use in cancer pain management.