PANSAID - PAracetamol and NSAID in combination: study protocol for a randomised trial

Fixed-Dose Combination of NSAIDs and Spasmolytic Agents in the Treatment of Different Types of Pain-A Practical Review

This review presents the most common disease entities in which combinations of NSAIDs and spasmolytic drugs are used to reduce pain. The benefits of fixed-dose combination products (FDCs) are that they improve the response in people with insufficient monotherapy. Using the synergy or additive effect of drugs, it is possible to obtain a significant therapeutic effect and faster action with the use of smaller doses of individual drugs. In addition, one active ingredient may counteract adverse reactions from the other. Another essential aspect of the use of FDCs is the improvement of medical adherence due to the reduction in the pill burden on patients. It is also possible to develop a fixed-dosed combination product de novo to address a new therapeutic claim and be protected by patents so that the manufacturer can obtain exclusive rights to sell a particular FDC or a formulation thereof. The proposed fixed-dose combinations should always be based on valid therapeutic principles and consider the combined safety profile of all active substances included in the medicinal product. This review aims to identify which combinations of NSAIDs and spasmolytics have been developed and tested and which combinations are still under development.

Participants with mild, moderate, or severe pain following total hip arthroplasty. A sub-study of the PANSAID trial on paracetamol and ibuprofen for postoperative pain treatment

OBJECTIVES

In this sub-study of the 'Paracetamol and Ibuprofen in Combination' (PANSAID) trial, in which participants were randomised to one of four different non-opioids analgesic regimen consisting of paracetamol, ibuprofen, or a combination of the two after planned primary total hip arthroplasty, our aims were to investigate the distribution of participants' pain (mild, moderate or severe), integrate opioid use and pain to a single score (Silverman Integrated Approach (SIA)-score), and identify preoperative risk factors for severe pain.

METHODS

We calculated the proportions of participants with mild (VAS 0-30 mm), moderate (VAS 31-60 mm) or severe (VAS 61-100 mm) pain and the SIA-scores (a sum of rank-based percentage differences from the mean rank in pain scores and opioid use, ranging from -200 to 200%). Using logistic regression with backwards elimination, we investigated the association between severe pain and easily obtainable preoperative patient characteristics.

RESULTS

Among 556 participants from the modified intention-to-treat population, 33% (95% CI: 26-42) (Group Paracetamol + Ibuprofen (PCM + IBU)), 28% (95% CI: 21-37) (Group Paracetamol (PCM)), 23% (95% CI: 17-31) (Group Ibuprofen (IBU)), and 19% (95% CI: 13-27) (Group Half Strength-Paracetamol + Ibuprofen (HS-PCM + IBU)) experienced mild pain 6 h postoperatively during mobilisation. Median SIA-scores during mobilisation were: Group PCM + IBU: -48% (IQR: -112 to 31), Group PCM: 40% (IQR: -31 to 97), Group IBU: -5% (IQR: -57 to 67), and Group HS-PCM + IBU: 6% (IQR: -70 to 74) (overall difference: p=0.0001). Use of analgesics before surgery was the only covariate associated with severe pain (non-opioid: OR 0.50, 95% CI: 0.29-0.82, weak opioid 0.56, 95% CI: 0.28-1.16, reference no analgesics before surgery, p=0.02).

CONCLUSIONS

Only one third of participants using paracetamol and ibuprofen experienced mild pain after total hip arthroplasty and even fewer experienced mild pain using each drug alone as basic non-opioid analgesic treatment. We were not able, in any clinically relevant way, to predict severe postoperative pain. A more extensive postoperative pain regimen than paracetamol, ibuprofen and opioids may be needed for a large proportion of patients having total hip arthroplasty. SIA-scores integrate pain scores and opioid use for the individual patient and may add valuable information in acute pain research.

The PANSAID randomized clinical trial: A pre-planned 1-year follow-up regarding harm

BACKGROUND

Limiting harm from postoperative pain treatment is important. However, long-term follow-up from acute pain trials are rare. The aim of the study was to provide long-term follow-up data regarding harm from the "Paracetamol and Ibuprofen in Combination" (PANSAID) trial.

METHODS

In this preplanned long-term follow-up study from the PANSAID trial, we used data from Danish national health registries (the Danish National Patient Registry and the Danish Civil Registration System) in addition to the 90-day follow-up in the original trial. The primary outcome was 1-year proportion of patients with one or more serious adverse events.

RESULTS

One-year follow-up was complete for 551 patients (99%). We found three additional patients with one or more serious adverse events in the 1-year follow-up compared with the 90-day follow-up. The relative risk of having one or more serious adverse event when randomized to ibuprofen compared with paracetamol was 1.40 (95% CI: 0.84-2.33, P = .20).

CONCLUSION

We found no statistically significant difference in 1-year serious adverse events between patients randomized to ibuprofen compared with paracetamol in patients having planned primary total hip arthroplasty. There were few additional events from the 90-day follow-up to the 1-year follow-up.

Benefits and harm of paracetamol and ibuprofen in combination for post-operative pain: Pre-planned subgroup analyses of the multicenter, randomized PANSAID trial

BACKGROUND

The "Paracetamol and Ibuprofen in Combination" (PANSAID) trial showed that combining paracetamol and ibuprofen resulted in lower opioid consumption than each drug alone and we did not find an increase in risk of harm when using ibuprofen vs paracetamol. The aim of this subgroup analysis was to investigate the differences in benefits and harms of the interventions in different subgroups. We hypothesized that the intervention effects would differ in subgroups with different risk of pain or adverse events.

METHODS

In these pre-planned subgroup analyses of the PANSAID trial population, we assessed subgroup heterogeneity in intervention effects between (a) subgroups (sex, age, use of analgesics, American Society of Anesthesiologists (ASA) score, and type of anesthesia) and morphine consumption, and (b) subgroups (sex, age, use of non-steroidal anti-inflammatory drugs (NSAIDs), and ASA score) and serious adverse events.

RESULTS

Test of interaction between age and the pairwise comparison between paracetamol 1 g vs paracetamol 0.5 g + ibuprofen 200 mg (P = .009) suggested lower morphine consumption in patients >65 years. However, post hoc analyses of related outcomes showed no interaction for this pairwise comparison. All other tests of interaction regarding both benefit and harm were not statistically significant.

CONCLUSION

These pre-planned subgroup analyses did not suggest that patients in the investigated subgroups benefitted differently from a basic non-opioid analgesic regimen consisting of paracetamol and ibuprofen. Further, there was no evidence of subgroup heterogeneity regarding harm and use of ibuprofen. Because of reduced statistical power in subgroup analyses, we cannot exclude clinically relevant subgroup heterogeneity.

Intravenous Paracetamol in Adjunct to Intravenous Ketoprofen for Postoperative Pain in Children Undergoing General Surgery: A Double-Blinded Randomized Study

Background and objectives: The combination of non-steroidal anti-inflammatory drugs and paracetamol is widely used for pediatric postoperative pain management, although the evidence of superiority of a combination over either drug alone is insufficient. We aimed to find out if intravenous (i.v.) paracetamol in a dose of 60 mg kg^-1 24 h^-¹, given in addition to i.v. ketoprofen (4.5 mg kg^-1 24 h^-¹), improves analgesia, physical recovery, and satisfaction with postoperative well-being in children and adolescents following moderate and major general surgery. Materials and Methods: Fifty-four patients were randomized to receive either i.v. paracetamol or normal saline as a placebo in adjunct to i.v. ketoprofen. For rescue analgesia in patients after moderate surgery, i.v. tramadol (2 mg kg^-¹ up two doses in 24 h), and for children after major surgery, i.v. morphine-patient-controlled analgesia (PCA) were available. The main outcome measure was the amount of opioid consumed during the first 24 h after surgery. Pain level at 1 and over 24 h, time until the resumption of normal oral fluid intake, spontaneous urination after surgery, and satisfaction with postoperative well-being were also assessed. Results: Fifty-one patients (26 in the placebo group and 25 in the paracetamol group) were studied. There was no difference in required rescue tramadol doses (n = 11 in each group) or 24-h morphine consumption (mean difference (95% CI): 0.06 (⁻0.17; 0.29) or pain scores between placebo and paracetamol groups. In patients given morphine-PCA, time to normal fluid intake was faster in the paracetamol than the placebo subgroup: median difference (95% CI): 7.5 (1.3; 13.7) h, p = 0.02. Parental satisfaction score was higher in the paracetamol than the placebo group (mean difference: ⁻1.3 (⁻2.5; ⁻0.06), p = 0.04). Conclusions: There were no obvious benefits to opioid requirement or analgesia of adding regular intravenous paracetamol to intravenous ketoprofen in used doses. However, intravenous paracetamol may contribute to faster recovery of normal functions and higher satisfaction with postoperative well-being.

Effect of Combination of Paracetamol (Acetaminophen) and Ibuprofen vs Either Alone on Patient-Controlled Morphine Consumption in the First 24 Hours After Total Hip Arthroplasty: The PANSAID Randomized Clinical Trial

IMPORTANCE

Multimodal postoperative analgesia is widely used but lacks evidence of benefit.

OBJECTIVE

Investigate beneficial and harmful effects of 4 nonopioid analgesics regimens.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, blinded, placebo-controlled, 4-group trial in 6 Danish hospitals with 90-day follow-up that included 556 patients undergoing total hip arthroplasty (THA) from December 2015 to October 2017. Final date of follow-up was January 1, 2018.

INTERVENTIONS

Participants were randomized to receive paracetamol (acetaminophen) 1000 mg plus ibuprofen 400 mg (n = 136; PCM + IBU), paracetamol 1000 mg plus matched placebo (n = 142; PCM), ibuprofen 400 mg plus matched placebo (n = 141; IBU), or half-strength paracetamol 500 mg plus ibuprofen 200 mg (n = 140; HS-PCM + IBU) orally every 6 hours for 24 hours postoperatively, starting 1 hour before surgery.

MAIN OUTCOMES AND MEASURES

Two co-primary outcomes: 24-hour morphine consumption using patient-controlled analgesia in pairwise comparisons between the 4 groups (multiplicity-adjusted thresholds for statistical significance, P < .0042; minimal clinically important difference, 10 mg), and proportion of patients with 1 or more serious adverse events (SAEs) within 90 days (multiplicity-adjusted thresholds for statistical significance, P < .025).

RESULTS

Among 559 randomized participants (mean age, 67 years; 277 [50%] women), 556 (99.5%) completed the trial and were included in the analysis. Median 24-hour morphine consumption was 20 mg (99.6% CI, 0-148) in the PCM + IBU group, 36 mg (99.6% CI, 0-166) for PCM alone, 26 mg (99.6% CI, 2-139) for IBU alone, and 28 mg (99.6% CI, 2-145) for HS-PCM + IBU. The median difference in morphine consumption between the PCM + IBU group vs PCM alone was 16 mg (99.6% CI, 6.5 to 24; P < .001); for the PCM-alone group vs HS-PCM + IBU, 8 mg (99.6% CI, -1 to 14; P = .001); and for the PCM + IBU group vs IBU alone, 6 mg (99.6% CI, -2 to 16; P = .002). The difference in morphine consumption was not statistically significant for the PCM + IBU group vs HS-PCM + IBU (8 mg [99.6% CI, -2 to 16]; P = .005) or for the PCM-alone group vs IBU alone (10 mg [99.6% CI, -2 to 16]; P = .004) after adjustment for multiple comparisons and 2 co-primary outcomes. There was no significant difference between the IBU-alone group vs HS-PCM + IBU (2 mg [99.6% CI, -10 to 7]; P = .81). The proportion of patients with SAEs in groups receiving IBU was 15%, and in the PCM-alone group, was 11%. The relative risk of SAE was 1.44 (97.5% CI, 0.79 to 2.64; P = .18).

CONCLUSIONS AND RELEVANCE

Among patients undergoing THA, paracetamol plus ibuprofen significantly reduced morphine consumption compared with paracetamol alone in the first 24 hours after surgery; there was no statistically significant increase in SAEs in the pooled groups receiving ibuprofen alone vs with paracetamol alone. However, the combination did not result in a clinically important improvement over ibuprofen alone, suggesting that ibuprofen alone may be a reasonable option for early postoperative oral analgesia.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02571361.

PANSAID-PAracetamol and NSAID in combination: detailed statistical analysis plan for a randomised, blinded, parallel, four-group multicentre clinical trial

Background

Effective postoperative pain management is essential for the rehabilitation of the surgical patient. The PANSAID trial evaluates the analgesic effects and safety of the combination of paracetamol and ibuprofen. This paper describes in detail the statistical analysis plan for the primary publication to prevent outcome reporting bias and data-driven analysis results.

Methods/design

The PANSAID trial is a multicentre, randomised, controlled, parallel, four-group clinical trial comparing the beneficial and harmful effects of different doses and combinations of paracetamol and ibuprofen in patients having total hip arthroplastic surgery. Patients, caregivers, physicians, investigators, and statisticians are blinded to the intervention. The two co-primary outcomes are 24-h consumption of morphine and proportion of patients with one or more serious adverse events within 90 days after surgery. Secondary outcomes are pain scores during mobilisation and at rest at 6 and 24 h postoperatively, and the proportion of patients with one or more adverse events within 24 h postoperatively.

Discussion

PANSAID will provide a large trial with low risk of bias regarding benefits and harms of the combination of paracetamol and ibuprofen used in a perioperative setting.

Trial registration

ClinicalTrials.org identifier: NCT02571361. Registered on 7 October 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2203-1) contains supplementary material, which is available to authorized users.