Evidence map›Paper›PMID 35435639›Full record

Trial reportClinical drug investigation2022

Efficacy and Safety of Tramadol Hydrochloride Twice-Daily Sustained-Release Bilayer Tablets with an Immediate-Release Component for Chronic Pain Associated with Knee Osteoarthritis: A Randomized, Double-Blind, Placebo-Controlled, Treatment-Withdrawal Study.

Shinichi Kawai, Satoshi Sobajima, Masashi Jinnouchi, Hideshi Nakano, Hideaki Ohtani, Mineo Sakata, Takeshi Adachi

Open access · hybridAbstract readMulticenter StudyRandomized Controlled Trial
In one paragraph

Trial report in Clinical drug investigation, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
6citing papers in PubMed, 1 pooled it
1.3field-weighted citation impact, top 21% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

6 citing papers in PubMed, 1 synthesis or guideline pooled it, 11 citations in OpenAlex.

  1. Pooled it
  2. Trial
  3. Article
  4. Article
  5. Article
  6. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 3 institutions in 1 country.

Shinichi KawaiDepartment of Inflammation and Pain Control Research, Toho University School of Medicine, 5-21-16 Omori-Nishi, Ota-ku, Tokyo, 143-8540, Japan. skawai@med.toho-u.ac.jp.ORCID http://orcid.org/0000-0002-3996-0039
Satoshi SobajimaSOBAJIMA Clinic, Osaka, Japan.
Masashi JinnouchiNishi Waseda Orthopedic Surgery, Tokyo, Japan.
Hideshi NakanoDepartment of Clinical Development, Nippon Zoki Pharmaceutical Co., Ltd., Osaka, Japan.
Hideaki OhtaniDepartment of Clinical Development, Nippon Zoki Pharmaceutical Co., Ltd., Osaka, Japan.
Mineo SakataDepartment of Clinical Development, Nippon Zoki Pharmaceutical Co., Ltd., Osaka, Japan.
Takeshi AdachiDepartment of Clinical Development, Nippon Zoki Pharmaceutical Co., Ltd., Osaka, Japan.
Nippon Zoki (Japan) · JPOsaka Nishi Clinic · JPToho University · JP

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

BACKGROUND AND

objectivesKnee osteoarthritis pain is a chronic form of pain for which conventional non-steroidal anti-inflammatory drugs may provide insufficient analgesia. Twice-daily tramadol hydrochloride (65% sustained-release/35% immediate-release) bilayer tablets are a novel formulation of tramadol developed for managing chronic pain. The objectives of this study were to examine the effectiveness and safety of this formulation in patients with chronic knee osteoarthritis pain.

methodsThis was a multicenter, randomized, placebo-controlled, double-blind, parallel-group, treatment-withdrawal study. Patients with a reduction in Numeric Rating Scale (NRS) for pain of ≥2 points during a 1-3-week, open-label, tramadol dose-escalation period (100-300 mg/day) were randomized to continue tramadol or switched to placebo for 4 weeks (double-blind period). Patients with inadequate efficacy (increase in NRS ≥2 points/patient request) were withdrawn. Outcomes included the time to inadequate analgesic efficacy from randomization (primary endpoint), the cumulative retention rate, and safety.

resultsOverall, 249 and 160 patients entered the dose-escalation and double-blind periods, respectively (tramadol 79; placebo 81). Kaplan-Meier analysis revealed superiority of tramadol (log-rank p = 0.042), and a hazard ratio of 0.50 (95% confidence interval [CI] 0.25-0.99). Documentation of an inadequate analgesic effect was less frequent in the tramadol group (15.4%, 95% CI 8.2-25.3% vs. 30.9%, 95% CI 21.1-42.1%). The cumulative retention rate was greater in the tramadol group (83.7% vs. 69.0%). Adverse events occurred in 80.6% (200/248) of patients in the open-label period, and in 38.5% (30/78) and 13.6% (11/81) of patients in the tramadol and placebo groups, respectively, in the double-blind period. Opioid-associated adverse events, such as nausea, vomiting, constipation, somnolence, and dizziness, were the most frequent events.

conclusionThis study demonstrated the analgesic efficacy and safety of sustained-release tramadol tablets with an immediate-release component for chronic knee osteoarthritis pain.

trial registrationJapicCTI-132103 (Japan Pharmaceutical Information Center; registration date February 25, 2015).

Indexed as

Chronic PainOsteoarthritis, KneeTramadolAnalgesicsAnalgesics, OpioidDelayed-Action PreparationsDouble-Blind MethodHumansTabletsAnalgesicsAnalgesics, OpioidDelayed-Action PreparationsTabletsTramadol

Identifiers

PMID35435639
PMCPMC9106645
OpenAlexW4223953258

What Socratic holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.