Targeted Therapeutics for Transthyretin Amyloid Cardiomyopathy

BACKGROUND

Deposition of wild-type or mutant transthyretin (TTR) amyloid fibrils in the myocardium causes TTR amyloid cardiomyopathy (ATTR-CM). Targeted therapeutics for ATTR-CM include TTR stabilizers (tafamidis and diflunisal) and oligonucleotide drugs (revusiran, patisiran, and inotersen). TTR stabilizers prevent dissociation of transthyretin tetramers. Transthyretin monomers can misfold and form amyloid fibrils. TTR stabilizers thereby limit amyloid fibrils development and deposition. Oligonucleotide drugs inhibit hepatic synthesis of transthyretin, which decreases transthyretin protein levels and thus the amyloid fibril substrate.

AREAS OF UNCERTAINTY

To study the safety and efficacy of targeted therapeutics in patients with ATTR-CM, we performed a pooled analysis. A random-effects model with the Mantel-Haenszel method was used to pool the data.

DATA SOURCES

A literature search was performed using PubMed, Cochrane CENTRAL, and Embase databases using the search terms "cardiac amyloidosis" AND "tafamidis" OR "patisiran" OR "inotersen" OR "revusiran" OR "diflunisal."

THERAPEUTIC ADVANCES

We identified 6 studies that compared targeted therapeutics with placebo. One study was stopped prematurely because of increased mortality in the targeted therapeutics arm. Pooled analysis included 1238 patients, of which 738 patients received targeted therapeutics and 500 patients received placebo. When compared with placebo, targeted therapeutics significantly reduced all-cause mortality [OR 0.39, 95% confidence interval (CI): 0.16-0.97, P = 0.04]. Only 2 studies reported the effect on cardiovascular-related hospitalizations. There was a trend toward an improvement in global longitudinal strain (mean difference -0.69, 95% CI: -1.44 to 0.05, P = 0.07). When compared with placebo, there was no increase in serious adverse events with targeted therapeutics (OR 1.06, 95% CI: 0.78-1.44, P = 0.72).

CONCLUSION

Evidence from the pooled analysis revealed targeted therapeutics improve survival and are well-tolerated. These findings suggest a potential role for targeted therapeutics in the treatment of patients with ATTR-CM.

The use of diflunisal for transthyretin cardiac amyloidosis: a review

Transthyretin cardiac amyloidosis (ATTR-CM) is caused by the accumulation of misfolded transthyretin (TTR) protein in the myocardium. Diflunisal, an agent that stabilizes TTR, has been used as an off-label therapeutic for ATTR-CM. Given limited data surrounding the use of diflunisal, a systematic review of the literature is warranted. We searched the PubMed, MEDLINE, and Embase databases for studies that reported on the use of diflunisal therapy for patients with ATTR-CM. We included English language studies which assessed the effect of diflunisal in adult patients with ATTR-CM who received diflunisal as primary treatment and reported clinical outcomes with emphasis on studies that noted the safety and efficacy of diflunisal in cardiac manifestations of ATTR amyloidosis. We excluded studies which did not use diflunisal therapy or used diflunisal therapy for non-cardiac manifestations of TTR amyloidosis. We also excluded case reports, abstracts, oral presentations, and studies with fewer than 10 subjects. Our search yielded 316 records, and we included 6 studies reporting on 400 patients. Non-comparative single-arm small non-randomized trials for diflunisal comprised 4 of the included studies. The 2 studies that compared diflunisal versus no treatment found improvements in TTR concentration, left atrial volume index, cardiac troponin I, and global longitudinal strain. Overall, diflunisal use was associated with decreased mortality and number of orthotopic heart transplant in ATTR-CM patients. Although a smaller number of patients had to stop treatment due to gastrointestinal side effects and transient renal dysfunction, there were no severe reactions reported in the studies included in our review. This systematic review supports the use of diflunisal for ATTR-CM. Additional long-term analyses and randomized clinical trials are needed to confirm these results.

[Specific pharmacological treatment guide for transthyretin amyloid cardiomyopathy, 2021]

This clinical practice guideline for treating transthyretin amyloid (ATTR) cardiomyopathy is based on the best available evidence of clinical effectiveness. The PICO format was used to generate a list of questions focused on the effectiveness and safety of the specific treatment of patients with ATTR cardiomyopathy. The search was conducted in PubMed, Cochrane and Epistemokus, between July-August 2020, and selected articles between 2000-2020, in English and Spanish. The level of evidence and recommendations were analyzed and classified by the GRADE system. The following drugs were included in the analysis: tafamidis, diflunisal, inotersen, patisiran y doxycycline and ursodeoxycholic acid. The expert panel had an agreement that tafamidis 80mg/daily is the only available drug with moderate evidence and weak recommendation for the reduction of total mortality, cardiovascular morbidity, heart failure hospitalization and progression of the disease in patients with ATTR cardiomyopathy and NYHA class = 3. In contrast, tafamidis 20 mg/daily had low-quality evidence in this group of patients. The expert panel did not recommend inotersen, patisiran and diflunisal in patients with ATTR cardiomyopathy due to the lack of supporting evidence, local drug availability, and the potential risk of toxicity. When patients did not have access to tafamidis, the expert panel stated a weak recommendation to use doxycycline and ursodeoxycholic acid in patients with ATTR cardiomyopathy.

A Review of Novel Agents and Clinical Considerations in Patients With ATTR Cardiac Amyloidosis

ABSTRACT

Transthyretin (ATTR) amyloidosis is a multisystem disease caused by organ deposition of amyloid fibrils derived from the misfolded transthyretin (TTR) protein. The purpose of this article is to provide an overview of current treatment regimens and summarize important considerations for each agent. A literature search was performed with the PubMed database for articles published through October 2020. Search criteria included therapies available on the market and investigational therapies used for ATTR amyloidosis treatment. Both prospective clinical trials and retrospective studies have been included in this review. Available therapies discussed in this review article are tafamidis, diflunisal, patisiran, and inotersen. Tafamidis is FDA approved for treatment of wild-type ATTR (ATTRwt) and hereditary ATTR (ATTRv) cardiomyopathy, and patisiran and inotersen are FDA approved for ATTRv polyneuropathy. Diflunisal does not have an FDA-labeled indication for amyloidosis but has been studied in ATTRv polyneuropathy and ATTRwt cardiomyopathy. Investigational therapies include a TTR stabilizer, AG10; 2 antifibril agents, PRX004 and doxycycline/tauroursodeoxycholic acid; and 2 gene silencers, vutrisiran and AKCEA-TTR-LRx; and clinical trials are ongoing. ATTR amyloidosis treatment selection is based on subtype and presence of cardiac or neurological manifestations. Additional considerations such as side effects, monitoring, and administration are outlined in this review.

Overview of treatments used in transthyretin-related hereditary amyloidosis: a systematic review

OBJECTIVE

To carry out a systematic review of the literature to analyse the efficacy and safety of treatments available or under investigation for amyloidosis due to mutations in the transthyretin gene (ATTR).

METHODS

A bibliographic search was carried out in the following electronic databases up to September 2017: PubMed, Cochrane Library and EMBASE. The inclusion criteria were: efficacy and/or safety studies conducted in humans, studies that included treatments, including treatments in the research phase, and studies that included 10 or more patients.

RESULTS

A total of 21 articles were included; 16 were clinical trials, eight of them (50%) phase III trials, and five were observational studies. Of the total number of studies selected, 11 were on tafamidis, four on diflunisal, two on liver transplantation, two on patisiran and two on other therapeutic alternatives. Of the 11 studies related to the drug, the pivotal trial, the results of its two extension studies and an additional post hoc analysis were selected. In addition, two phase III trials were included in specific populations, two phase II studies, one safety study and two observational studies. Regarding the four included studies related to the drug, one was the pivotal trial that gave the indication to diflunisal, another a safety summary of the pivotal trial, and the other two trials were carried out in specific populations, one in a Japanese population and another phase I trial in cardiac amyloidosis in the USA. As far as other alternatives are concerned, of the six studies included in this section, two were related to liver transplantation, two to patisiran and two to different therapeutic alternatives.

CONCLUSIONS

Sufficient evidence has not been found that demonstrates superiority among the available oral alternatives, diflunisal or tafamidis, in the treatment of ATTR. Direct comparisons between both drugs and pharmacoeconomic studies would be necessary to select the most efficient treatment.

Pharmacological treatment for familial amyloid polyneuropathy

BACKGROUND

Disease-modifying pharmacological agents for transthyretin (TTR)-related familial amyloid polyneuropathy (FAP) have become available in the last decade, but evidence on their efficacy and safety is limited. This review focuses on disease-modifying pharmacological treatment for TTR-related and other FAPs, encompassing amyloid kinetic stabilisers, amyloid matrix solvents, and amyloid precursor inhibitors.

OBJECTIVES

To assess and compare the efficacy, acceptability, and tolerability of disease-modifying pharmacological agents for familial amyloid polyneuropathies (FAPs).

SEARCH METHODS

On 18 November 2019, we searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase. We reviewed reference lists of articles and textbooks on peripheral neuropathies. We also contacted experts in the field. We searched clinical trials registries and manufacturers' websites.

SELECTION CRITERIA

We included randomised clinical trials (RCTs) or quasi-RCTs investigating any disease-modifying pharmacological agent in adults with FAPs. Disability due to FAP progression was the primary outcome. Secondary outcomes were severity of peripheral neuropathy, change in modified body mass index (mBMI), quality of life, severity of depression, mortality, and adverse events during the trial.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology.

MAIN RESULTS

The review included four RCTs involving 655 people with TTR-FAP. The manufacturers of the drugs under investigation funded three of the studies. The trials investigated different drugs versus placebo and we did not conduct a meta-analysis. One RCT compared tafamidis with placebo in early-stage TTR-FAP (128 randomised participants). The trial did not explore our predetermined disability outcome measures. After 18 months, tafamidis might reduce progression of peripheral neuropathy slightly more than placebo (Neuropathy Impairment Score (NIS) in the lower limbs; mean difference (MD) -3.21 points, 95% confidential interval (CI) -5.63 to -0.79; P = 0.009; low-certainty evidence). However, tafamidis might lead to little or no difference in the change of quality of life between groups (Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) total score; MD -4.50 points, 95% CI -11.27 to 2.27; P = 0.19; very low-certainty evidence). No clear between-group difference was found in the numbers of participants who died (risk ratio (RR) 0.65, 95% CI 0.11 to 3.74; P = 0.63; very low-certainty evidence), who dropped out due to adverse events (RR 1.29, 95% CI 0.30 to 5.54; P = 0.73; very low-certainty evidence), or who experienced at least one severe adverse event during the trial (RR 1.16, 95% CI 0.37 to 3.62; P = 0.79; very low-certainty evidence). One RCT compared diflunisal with placebo (130 randomised participants). At month 24, diflunisal might reduce progression of disability (Kumamoto Score; MD -4.90 points, 95% CI -7.89 to -1.91; P = 0.002; low-certainty evidence) and peripheral neuropathy (NIS plus 7 nerve tests; MD -18.10 points, 95% CI -26.03 to -10.17; P < 0.001; low-certainty evidence) more than placebo. After 24 months, changes from baseline in the quality of life measured by the 36-Item Short-Form Health Survey score showed no clear difference between groups for the physical component (MD 6.10 points, 95% CI 2.56 to 9.64; P = 0.001; very low-certainty evidence) and the mental component (MD 4.40 points, 95% CI -0.19 to 8.99; P = 0.063; very low-certainty evidence). There was no clear between-group difference in the number of people who died (RR 0.46, 95% CI 0.15 to 1.41; P = 0.17; very low-certainty evidence), in the number of dropouts due to adverse events (RR 2.06, 95% CI 0.39 to 10.87; P = 0.39; very low-certainty evidence), and in the number of people who experienced at least one severe adverse event (RR 0.77, 95% CI 0.18 to 3.32; P = 0.73; very low-certainty evidence) during the trial. One RCT compared patisiran with placebo (225 randomised participants). After 18 months, patisiran reduced both progression of disability (Rasch-built Overall Disability Scale; least-squares MD 8.90 points, 95% CI 7.00 to 10.80; P < 0.001; moderate-certainty evidence) and peripheral neuropathy (modified NIS plus 7 nerve tests - Alnylam version; least-squares MD -33.99 points, 95% CI -39.86 to -28.13; P < 0.001; moderate-certainty evidence) more than placebo. At month 18, the change in quality of life between groups favoured patisiran (Norfolk QOL-DN total score; least-squares MD -21.10 points, 95% CI -27.20 to -15.00; P < 0.001; low-certainty evidence). There was little or no between-group difference in the number of participants who died (RR 0.61, 95% CI 0.21 to 1.74; P = 0.35; low-certainty evidence), dropped out due to adverse events (RR 0.33, 95% CI 0.13 to 0.82; P = 0.017; low-certainty evidence), or experienced at least one severe adverse event (RR 0.91, 95% CI 0.64 to 1.28; P = 0.58; low-certainty evidence) during the trial. One RCT compared inotersen with placebo (172 randomised participants). The trial did not explore our predetermined disability outcome measures. From baseline to week 66, inotersen reduced progression of peripheral neuropathy more than placebo (modified NIS plus 7 nerve tests - Ionis version; MD -19.73 points, 95% CI -26.50 to -12.96; P < 0.001; moderate-certainty evidence). At week 65, the change in quality of life between groups favoured inotersen (Norfolk QOL-DN total score; MD -10.85 points, 95% CI -17.25 to -4.45; P < 0.001; low-certainty evidence). Inotersen may slightly increase mortality (RR 5.94, 95% CI 0.33 to 105.60; P = 0.22; low-certainty evidence) and occurrence of severe adverse events (RR 1.48, 95% CI 0.85 to 2.57; P = 0.16; low-certainty evidence) compared to placebo. More dropouts due to adverse events were observed in the inotersen than in the placebo group (RR 8.57, 95% CI 1.16 to 63.07; P = 0.035; low-certainty evidence). There were no studies addressing apolipoprotein AI-FAP, gelsolin-FAP, and beta-2-microglobulin-FAP.

AUTHORS' CONCLUSIONS

Evidence on the pharmacological treatment of FAPs from RCTs is limited to TTR-FAP. No studies directly compare disease-modifying pharmacological treatments for TTR-FAP. Results from placebo-controlled trials indicate that tafamidis, diflunisal, patisiran, and inotersen may be beneficial in TTR-FAP, but further investigations are needed. Since direct comparative studies for TTR-FAP will be hampered by sample size and costs required to demonstrate superiority of one drug over another, long-term non-randomised open-label studies monitoring their efficacy and safety are needed.

[Newly developed drug therapies for familial amyloid polyneuropathy: diflunisal and tafamidis]

Familial amyloid polyneuropathy (FAP) is an autosomal dominant genetic disorder with systemic deposition of amyloid fibrils, and is characterized by progressive sensory, motor, and autonomic polyneuropathy. FAP was considered a rare endemic disease; however, its worldwide incidence is much higher than previously recognized. Until recently, liver transplantation was the only effective treatment for FAP. However, liver transplantation has a number of limitations, including a shortage of donors and a requirement for surgery for both the recipient and living donor. Furthermore, a large number of the patients are not good transplant candidates because of their age and/or advanced disease status. Recently, the clinical effects of two transthyretin tetramer stabilizers, diflunisal and tafamidis, were demonstrated in randomized clinical trials, and tafamidis was approved for the treatment of FAP in European countries in 2011 and Japan in 2013.

Repurposing diflunisal for familial amyloid polyneuropathy: a randomized clinical trial

IMPORTANCE

Familial amyloid polyneuropathy, a lethal genetic disease caused by aggregation of variant transthyretin, induces progressive peripheral nerve deficits and disability. Diflunisal, a nonsteroidal anti-inflammatory agent, stabilizes transthyretin tetramers and prevents amyloid fibril formation in vitro.

OBJECTIVE

To determine the effect of diflunisal on polyneuropathy progression in patients with familial amyloid polyneuropathy.

DESIGN, SETTING, AND PARTICIPANTS

International randomized, double-blind, placebo-controlled study conducted among 130 patients with familial amyloid polyneuropathy exhibiting clinically detectable peripheral or autonomic neuropathy at amyloid centers in Sweden (Umeå), Italy (Pavia), Japan (Matsumoto and Kumamoto), England (London), and the United States (Boston, Massachusetts; New York, New York; and Rochester, Minnesota) from 2006 through 2012.

INTERVENTION

Participants were randomly assigned to receive diflunisal, 250 mg (n=64), or placebo (n=66) twice daily for 2 years.

MAIN OUTCOMES AND MEASURES

The primary end point, the difference in polyneuropathy progression between treatments, was measured by the Neuropathy Impairment Score plus 7 nerve tests (NIS+7) which ranges from 0 (no neurological deficits) to 270 points (no detectable peripheral nerve function). Secondary outcomes included a quality-of-life questionnaire (36-Item Short-Form Health Survey [SF-36]) and modified body mass index. Because of attrition, we used likelihood-based modeling and multiple imputation analysis of baseline to 2-year data.

RESULTS

By multiple imputation, the NIS+7 score increased by 25.0 (95% CI, 18.4-31.6) points in the placebo group and by 8.7 (95% CI, 3.3-14.1) points in the diflunisal group, a difference of 16.3 points (95% CI, 8.1-24.5 points; P < .001). Mean SF-36 physical scores decreased by 4.9 (95% CI, -7.6 to -2.2) points in the placebo group and increased by 1.5 (95% CI, -0.8 to 3.7) points in the diflunisal group (P < .001). Mean SF-36 mental scores declined by 1.1 (95% CI, -4.3 to 2.0) points in the placebo group while increasing by 3.7 (95% CI, 1.0-6.4) points in the diflunisal group (P = .02). By responder analysis, 29.7% of the diflunisal group and 9.4% of the placebo group exhibited neurological stability at 2 years (<2-point increase in NIS+7 score; P = .007).

CONCLUSIONS AND RELEVANCE

Among patients with familial amyloid polyneuropathy, the use of diflunisal compared with placebo for 2 years reduced the rate of progression of neurological impairment and preserved quality of life. Although longer-term follow-up studies are needed, these findings suggest benefit of this treatment for familial amyloid polyneuropathy.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00294671.

Diflunisal for ATTR cardiac amyloidosis

Transthyretin (TTR) cardiac amyloidosis is an important, often under-recognized and potentially modifiable cause of heart failure with a preserved ejection fraction. The only proven treatment is liver or combined heart/liver transplantation, which, although effective, is not suitable for the vast majority of older adults with this condition. Diflunisal, a nonsteroidal anti-inflammatory drug, can stabilize the TTR tetramer in vitro and may prevent misfolding monomers and dimers from forming amyloid deposits in the heart. It is one of two small molecules assessed in animal safety studies and human clinical trials of TTR polyneuropathy. The authors conducted a single-arm, open-label investigation with a mean follow-up of 0.9 ± 0.3 years to determine the safety and efficacy of diflunisal administration in a cohort of 13 patients with confirmed wild-type or mutant TTR cardiac amyloidosis. Diflunisal was well tolerated from a hematologic standpoint, although a 6% decline in estimated glomerular filtration rate was noted. Therapy was discontinued in one patient who rapidly developed volume overload. There was no significant mean change in cardiac structure (left ventricular mass: -53 g/m(2) change, P=.36), function (ejection fraction: -2% change, P=.61), or biomarkers (Troponin I: +0.03 ng/mL, P=.08; BNP: +93 pg/mL change, P=.52) during the course of therapy. These data suggest that at low dosages and with careful monitoring, diflunisal can be safely administered to compensated patients with cardiac TTR amyloidosis. Further study in a randomized placebo-controlled trial is warranted.

[Familial amyloid polyneuropathies: therapeutic issues]

Patients with familial amyloidpolyneuropathies (FAP) require multidisciplinary neurologic and cardiologic management, including specific treatments to control the progression of systemic amyloidogenesis, symptomatic treatment of peripheral and autonomic neuropathies, and management of severe organ involvement (heart, eyes, kidneys). The first-line specific treatment of choice for met30 TTR-FAP is liver transplantation (LT) which suppresses the main source of mutant TTR, halts the progression of neuropathy in 70% of cases, and doubles the median survival time. Dual kidney-liver or heart-liver transplantation may be appropriate for patients with severe renal or cardiac failure. Tafamidis (Vyndaqel(R), Pfizer), a novel stabilizer of tetrameric TTR, has shown short-term effectiveness in slowing the progression of peripheral neuropathy in very early stages of met30 TTR-FAP This drug should thus be proposed for stage 1 symptomatic polyneuropathy. Other innovative medicines (RNA interference, antisense oligonucleotides) have been developed to block hepatic production of both mutant and wildtype TTR (noxious in late-onset forms of NAH after age 50 years), and to remove amyloid deposits (monoclonal anti-SAP). Clinical trials should first include patients with late-onset FAP or non-met30 TTR-FAP who are less responsive to LT7 and patients in whom Vyndaqel(R) is ineffective or inappropriate. Initial and periodic cardiac assessment is necessary, as cardiac impairment is inevitable and largely responsible for mortality. Symptomatic treatment is crucial to improve these patients' quality of life. Familial screening for carriers of the TTR gene mutation and regular clinical examination are essential to detect disease onset and to start specific therapy in a timely manner.

A comparison of pre-emptive analgesic efficacy of diflunisal and lornoxicam for postoperative pain management: a prospective, randomized, single-blind, crossover study

Diflunisal and lornoxicam are currently available non-steroidal anti-inflammatory drugs (NSAIDs) that have been shown to be effective to various degrees in pain relief when administered either pre-emptively or postoperatively. The pre-emptive analgesic efficacy of diflunisal 1000 mg was compared with that of lornoxicam 16 mg in 40 ASA I patients undergoing surgical removal of bilateral impacted third molars. The impacted third molar teeth on one side were removed at the first surgical appointment using one of the two drug regimens being assessed and the teeth on the contralateral side were removed at a second appointment using the alternate drug regimen; all operations were performed by the same surgeon. Acetaminophen up to 2000 mg daily was provided as rescue medication. The postoperative rescue analgesic consumption was recorded and pain scores were evaluated with a visual analogue scale at 2, 4, 6, 12 and 24h postoperatively. No statistically significant differences were found between groups with respect to rescue analgesic consumption and postoperative pain scores. Pre-emptive administration of both NSAIDs proved to be effective in the management of pain following the surgical removal of impacted third molar teeth.

Drug Insight: emerging therapies for amyloidosis

Amyloidosis is a clinical disorder caused by extracellular deposition of proteins that are normally soluble as insoluble, abnormal fibrils that impair organ function. More than 20 unrelated proteins can form amyloid fibrils in vivo. All fibrils share cross-beta core structure and pathognomonic red-green birefringence when viewed under cross-polarized light after staining with Congo red. Amyloidosis can be acquired or hereditary, localized or systemic, and is classified according to the fibril precursor protein. Local amyloid deposition occurs in the brain in Alzheimer's disease and in the pancreas in maturity-onset diabetes, but a direct role in the pathogenesis of these diseases remains unproven. Systemic amyloidosis, with amyloid deposits in the viscera, blood vessel walls and connective tissues, is usually fatal and is the cause of about one death per thousand in developed countries. Recent elucidation of fundamental aspects of the pathogenesis of amyloidosis, and developments in diagnosis and monitoring of this disorder have greatly improved outcome for patients. Several exciting novel therapeutic strategies, reviewed in this article, are in development. These include interference with different stages of fibrillogenesis and enhancement of clearance of amyloid deposits.

A study of the comparative efficacy of three common analgesics in the control of pain after third molar surgery under local anaesthesia

BACKGROUND

The aim of this study was to evaluate the comparative efficacy of three commonly used analgesics (Panadeine, Diflunisal and Etodolac) in the control of pain after third molar surgery under local anaesthesia.

METHODS

A randomized control study. Outcome of primary efficacy was judged by overall assessment of the area under the curve of graphs for pain intensity, measured from serial visual analogue scales over a 24-hour period. Other measures of efficacy included the number (per cent) of patients who took 'additional' analgesics and the incidence of adverse effects occurring in each treatment group over the study period.

RESULTS

The three drugs were effective in the control of post-operative pain (p<0.01). Variations in pain intensity and the use of additional medication between the treatment groups were observed over the study period. The Diflunisal group experienced less pain than the Panadeine or Etodolac group (p<0.01). Furthermore, a lesser number of those in the Diflunisal group used additional medication compared to the other two groups (p<0.01). The incidence of side effects from all three drugs was low.

CONCLUSION

Diflunisal is superior in the control of pain following third molar surgery under local anaesthesia than either Panadeine or Etodolac, and has few side effects.

Interappointment emergencies in teeth with necrotic pulps

The incidence of interappointment emergencies in symptomatic and asymptomatic teeth with necrotic pulps was evaluated, and severity of flare-ups was determined by a quantitative method using a flare-up index. There were no significant differences in the incidence of flare-ups attributable to gender, age, diameter of lesion, taking analgesics, placebos, or no medication, or preoperative symptomatic or asymptomatic tooth diagnoses (p > 0.05). There were significantly more painful flare-ups in mandibular teeth than in maxillary (p < 0.05).

A comparison of two nonsteroidal antiinflammatory drugs (diflunisal versus dipyrone) in the treatment of moderate to severe cancer pain: a randomized crossover study

The efficacy of diflunisal in cancer pain was evaluated and compared with dipyrone. Diflunisal was given at the dosage of 500 mg perorally twice a day, and dipyrone was given at the dosage of 500 mg perorally three times a day. Duration of each treatment was 7 days; after a 12-hour wash-out period, patients were given the other drug for another 7 days. A total of 50 patients were enrolled in the study. Pain intensity was assessed by 10-point visual analog scale (VAS). Patients who had a VAS score higher than 5 were included. A total of 47 patients were evaluable. Initial VAS score was a mean of 8.57+/-1.33. Diflunisal reduced the pain score by a mean of 4.65+/-3.10, whereas dipyrone reduced the pain score by a mean of 3.25 < or = 2.85 (p < 0.001). Patients were also analyzed in three subgroups according to the presence of nonmetastatic, metastatic, and bone metastatic diseases. In each of these subgroups, diflunisal reduced the pain score more than dipyrone; however, the difference was statistically significant only in patients who had bone metastasis. Adverse reactions were rare and acceptable with both drugs. Diflusinal is superior to dipyrone at this dosage and schedule in the treatment of moderate to severe cancer pain.

Clinical effects of diflunisal and paracetamol in impacted mandibular third molar surgery

A double-blind, randomized, cross-over study to compare diflunisal and paracetamol for postoperative pain, swelling and trismus relief following impacted mandibular third molar surgery was designed. 25 patients received one of the drugs at one visit and the alternative at the other visit. First doses were given two hours preoperatively and continued twice daily for five days. The study was carried out to determine the effect of preoperatively used diflunisal on postoperative pain after surgical removal of the third molars as compared to paracetamol used in a similar manner. The degree of impaction, pain, swelling and mouth opening were assessed by standardized methods and possible adverse effects were also recorded separately. Statistical analysis was carried out by "Student's t test". (p < 0.01 statistically significant).

Comparison of the analgesic effects of diflunisal and paracetamol in the treatment of postoperative dental pain

The search for new effective analgesics without unwanted effects on the coagulation mechanism and a longer duration of activity has been intensified. One such development is diflunisal and the aim of this study was to compare the analgesic effect of diflunisal with that of paracetamol. A combined single dose (500-mg tablets), double-blind, randomized, controlled design in out-patients (n = 104) with moderate or severe pain caused by the surgical removal of impacted mandibular third molars was used in this study. Pain intensity and relief were assessed postoperatively for 8h using category-rating scales. The results showed a statistically significant difference in favour of diflunisal in each and every parameter used in determining the efficacy of the treatment.

Treatment modalities for soft tissue injuries of the ankle: a critical review

We reviewed the English language medical literature on soft tissue injuries of the ankle published between 1966 and 1993. There were 150 articles reviewed of which 84 dealt substantially with ankle soft tissue injuries. The papers were analyzed for quality and it was found that there were significant weaknesses throughout the literature. This related particularly to randomization, blinded assessment, and outcome measures. The results of the treatment of 32,025 patients were reported in 84 studies. We were unable to gather sufficient data from these studies to perform a statistical analysis of the different forms of treatment. Our conclusions were that nonsteroidal antiinflammatory drugs shortened the time period to recovery and were associated with less pain. Active mobilization appeared to be the treatment of choice. Studies also showed that cryotherapy was of benefit and diapulse may be helpful. There was insufficient evidence to conclude that enzyme treatment, topical gels, ultrasound or diathermy, joint aspiration of injection were of benefit. Overall the literature would substantiate active mobilization following ankle sprains with judicious early use of nonsteroidal antiinflammatory drugs and the use of cryotherapy and diapulse in the treatment of ankle injuries. Our study suggests further investigations need to be carried out into the effectiveness and outcomes following alternative forms of therapy for ankle injuries.

Analgesic efficacy of non-steroidal anti-inflammatory drugs in experimental pain in humans

1. The aim of this study was to establish a simple and reliable experimental pain model that could distinguish the analgesic effects of non-steroidal anti-inflammatory drug (NSAID) treatment from placebo in human volunteers. 2. The reproducibility and reliability over time of subject pain ratings was compared using cutaneous electrical stimuli applied to either the thenar eminence or the ear lobe at varying intensities and modes. Subjects were asked to respond firstly, when the stimulus became clearly sharp and painful ('first pain') and secondly, when the sensation became deep and burning and no further increase in stimulus intensity could be tolerated ('second pain'). 3. Constant voltage stimuli were found to be more reproducible than constant current stimuli. Both phasic (intermittent) and tonic (continuous) stimulation modalities produced 'first' and 'second pain' sensations. The latter sensation was more reproducible, and was perceived as a burning pain which is akin to clinical pain. 4. Analgesics from the NSAID class were found to attenuate reliably only 'second pain' sensations. The analgesic effects of ibuprofen (ibuprofen vs placebo: 0.12 +/- 0.09 vs 0.02 +/- 0.07 volt h(-1), P = 0.03; 95% confidence interval for differences (CI): 0.03-0.18) and diflunisal (diflunisal vs placebo: 0.29 +/- 0.40 vs 0.005 +/- 0.27 volt h(-1), P = 0.0001; CI: 0.168-0.407), respectively, could be distinguished from placebo.

Diflunisal--a long-acting non-steroidal anti-inflammatory drug. A review of its pharmacology and effectiveness in management of postoperative dental pain

Diflunisal is frequently used for management of postoperative dental pain as it has some advantages over other commonly used non-steroidal anti-inflammatory drugs including improved analgesia, a prolonged duration of action lasting up to 12 hours, and a low incidence of side effects. The aim of this paper is to review the relevant pharmacologic actions of the drug including its mechanism of action in suppressing the inflammatory response, and indications for its use in dentistry. Diflunisal can be safely recommended for the dental patient following oral surgery and exodontia, periodontal surgery and endodontic surgery.

Pre-operative diflunisal for pain relief following third molar surgery under general anaesthesia

In order to find out whether long-acting non-narcotic analgesics given pre-operatively reduce the post-operative pain and decrease the narcotic analgesic requirements following third molar surgery under general anaesthesia, thirty Hong Kong Chinese patients undergoing this procedure were randomly given either diflunisal or placebo one hour prior to anaesthesia. Pain reduction was monitored for ten hours from the end of surgery using visual analogue scales. Except in the first hour, pain reduction at each hour was significantly better in the diflunisal group than in the placebo group. Furthermore, only one patient required narcotic analgesics in the diflunisal group compared with five in the placebo group. In patients who had multiple tooth sectioning or very difficult surgery of one or both lower third molars, the requirement for post-operative analgesics was high in the placebo group.

Comparative multiple-dose study of ketorolac tromethamine and diflunisal for pain following orthopaedic surgery

A total of 100 patients were enrolled after orthopaedic surgery in a multiple-dose, randomized, double-blind, parallel-group study to compare the analgesic efficacy and safety of 10 mg ketorolac tromethamine given orally four times daily for 3 days with 500 mg diflunisal given orally twice daily plus placebo twice daily for 3 days. Ketorolac was significantly (P = 0.04) superior to diflunisal in reducing the pain severity during the first 9 h of treatment; a difference possibly related to the more flexible dosage regimen of ketorolac. Patients and the investigator, however, rated ketorolac and diflunisal as being equally effective in terms of the overall drop in severity of pain and pain relief at the end of days 1, 2 and 3. Ketorolac-treated patients reported a total of nine adverse events and diflunisal-treated patients reported 13. It is concluded that in the treatment of acute post-operative pain a drug with a more flexible dosage regimen may provide superior pain relief.

Inability to interpret toxic salicylate levels in patients taking aspirin and diflunisal

Diflunisal, a nonsteroidal antiinflammatory drug, is not metabolized to the free salicylate moiety, but yields serum salicylate levels. We describe 2 patients who unexpectedly had toxic range serum salicylate levels while taking diflunisal and aspirin for rheumatoid arthritis. Diflunisal is measured by standard salicylate assays, a fact not widely appreciated. Serum salicylate levels by these assays cannot be used to determine salicylate toxicity when a patient is taking both aspirin and diflunisal. High pressure liquid chromatography can be used to distinguish true salicylate toxicity from interference with diflunisal.

Evaluation of postoperative diflunisal for periodontal surgery pain

This study evaluated the efficacy of diflunisal as an analgesic to reduce postoperative pain when administered immediately following periodontal surgery. It was a continuation of a previous investigation which tested the effectiveness of diflunisal, administered preoperatively, in reducing periodontal surgical pain. Twenty-four patients were divided into two groups in a double-blind, random manner. Group 1 received postoperative therapeutic doses of diflunisal equal to the preoperative doses administered in the first study, and Group 2 received postoperative placebos. The postoperative diflunisal group reported significantly less pain (P less than or equal to 0.05) than the postoperative placebo group, and used rescue medication significantly less often (P less than or equal to 0.05). There was no significant difference in postsurgical discomfort between diflunisal administered postoperatively in this study and equal dosages of diflunisal administered preoperatively as previously reported.

Does midazolam sedation in oral surgery affect the potency or duration of diflunisal analgesia?

A randomized cross-over study was carried out to determine whether midazolam in doses used for conscious sedation had any effect on the potency or duration of diflunisal, a non-narcotic analgesic used for postoperative pain in oral surgery. Thirty-two Hong Kong Chinese patients of either sex, aged between 16 and 28 years, were given either midazolam to supplement local anaesthesia or local anaesthesia alone at one visit and the alternative at the other visit, for surgical removal of bilateral symmetrically impacted third molars. Surgery was carried out on one side only at each visit. Diflunisal was given for postoperative pain relief. Midazolam had no effect on the potency or duration of action of diflunisal. Independent of the method, more patients had better pain relief following the second procedure than following the first, probably due to a degree of adaptation to the pain, at the second visit.

[Use of NSAIDS in dentistry: double blind controlled study of Diflunisal versus ASA]

As a conclusion to the results obtained during our studies, we can say that both drugs provided fast and accurate antalgic anti-inflammatory characteristics. Diflunisal has however shown a slightly more powerful and larger lasting antalgic action which provides a higher tolerance level than the drug which was used as a comparison.

Diflunisal versus naproxen in the management of rheumatoid arthritis

Diflunisal (500 mg orally, twice daily) and naproxen (375 mg orally, twice daily) were compared for efficacy and tolerability in a 12-week open-label study in 33 patients with active rheumatoid arthritis (RA). Both drugs resulted in marked reduction in the number of swollen, tender, and painful joints and comparable improvement in patients' assessment of disease activity and pain. There were no significant differences between the two medications in the measured indices of disease activity. No adverse experiences were reported by patients in either treatment group. The results indicate that both diflunisal and naproxen were equally effective and that both agents are generally well tolerated in this group of patients with RA.

A comparison of the efficacy and tolerability of diflunisal and dextropropoxyphene napsylate with acetaminophen in the management of mild to moderate pain after arthroscopy of the knee

We conducted an open-label randomized clinical trial comparing the efficacy and tolerability of diflunisal and dextropropoxyphene napsylate with acetaminophen (DPN-A) in the management of mild to moderate pain following arthroscopic surgery of the knee. Patients used a self-rating pain scale to evaluate the analgesia provided by each medication. Twenty-six patients completed the study; 12 received diflunisal and 14 received DPN-A. The physicians found no significant differences between the two groups in their preoperative or postoperative assessment of pain, tenderness, swelling, and active range of motion. There were no statistically significant differences between the two groups' mean pain scores or assessment of the overall efficacy of their respective drugs. No patient in either treatment group reported any adverse effects.

Low sulpho-conjugated steroid hormone levels in systemic lupus erythematosus (SLE)

In a clinical study the blood levels of dehydroepiandrosterone sulphate (DHEAS), pregnenolone sulphate (5-PS), testosterone sulphate (TS) and their respective unconjugated steroids were measured in: 20 patients with systemic lupus erythematosus (SLE) who were receiving either no treatment (11 patients) or else treatment with chloroquine (9 patients), in some cases combined with non-steroidal anti-inflammatory drugs (NSAIDs); in 26 patients receiving corticosteroid (Prednisolone) treatment; and in healthy men and women. The patients not on corticosteroid exhibited substantially reduced DHEAS, 5-PS and TS levels (geom. mean: 2300 vs. normal 4300 nmol/l DHEAS; 200 vs. 320 nmol/l 5-PS; and 120 vs. 360 nmol/l TS; p less than 0.001), irrespective of the difference in sex, age or chloroquine treatment. The patients on corticosteroid treatment displayed a similar pattern of levels, but the reduction was much more marked than in the patients not on the steroid (geom. mean: 610 nmol/l DHEAS, 55 nmol/l 5-PS; and 35 nmol/l TS; p less than 0.001). No consistent changes were observed in the unconjugated steroid levels, although they were also reduced by the treatment with prednisolone. The data indicate that a deficiency in sulpho-conjugated steroids is a permanent feature of patients with SLE and that this is accentuated by the administration of corticosteroid derivatives. Further studies are needed to establish the pathophysiological significance of these findings.

A double-blind single-dose evaluation of the relative analgesic efficacy and safety of carprofen in the treatment of postoperative pain after oral surgery

A clinical study to evaluate the analgesic efficacy of carprofen was conducted at the University of Colorado School of Dentistry. In a 6-month period, 248 patients underwent the surgical removal of wisdom teeth for analysis of postoperative pain relief.

Diflunisal and ibuprofen: effects on gastric and duodenal mucosa in patients with osteoarthritis

Patients with osteoarthritis make up the largest group of users of nonsteroidal anti-inflammatory drugs (NSAIDs), but the effects of these agents on the gastrointestinal mucosa of such patients have not been well studied. This article describes a short-term comparison of two widely used NSAIDs, diflunisal and ibuprofen, in patients requiring these medications for their osteoarthritis. Efficacy, tolerability, and endoscopically documented effects of these drugs on the gastric and duodenal mucosa were assessed. Consenting, eligible patients were randomly assigned to one of the two study drugs for a two-week course. Clinical assessments were made after each week of treatment. Fiberoptic endoscopy and laboratory tests were performed before and after the treatment period. Thirty patients completed the study: 16 received diflunisal and 14 received ibuprofen. Similar improvements in pain, joint mobility, functional capacity, and joint swelling and tenderness were observed in both treatment groups. Transient, mild abdominal cramping was reported by two patients in each group; one patient receiving ibuprofen complained of transient dizziness. No patient withdrew from the study because of side effects. Follow-up endoscopy revealed slight (grade 1) changes in the gastric mucosa of two patients in each treatment group. An additional patient in the ibuprofen group had gastric erosions (grade 2) at the end of the study. Endoscopic changes were not correlated with symptoms. Diflunisal and ibuprofen were found to be similarly effective and well tolerated in the treatment of osteoarthritis. Their use may be associated with some gastrointestinal side effects even during short-term use.

A comparison of paracetamol and diflunisal for pain control following 3rd molar surgery

A double-blind randomised cross-over study to compare 2 regimes of paracetamol and diflunisal for postoperative pain relief following 3rd molar surgery was designed. 35 patients received one of the regimes at one visit and the alternative at the other visit. Both drugs, namely a single dose of 500 mg of diflunisal given preoperatively or 2 doses of 1000 mg of paracetamol, given preoperatively and 4 h postoperatively, produced adequate pain relief, without the need for supplementary analgesics during the 10-h test period. The differences in the mean overall pain scores in the 2 regimes were not statistically significant.

Acute back pain and spasm. A controlled multicenter trial of combined analgesic and antispasm agents

A double-blind, 18-center, balanced trial of diflunisal vs. cyclobenzaprine HCl vs. these two drugs combined vs. placebo produced complete results from 175 patients. They had sought treatment at the cooperating centers for acute painful spasms of the back within a day or two of trauma or strain. Global results over the 7 to 10 days of observations revealed a clinically and statistically significant superiority of the combined therapy by Day 4 (P = 0.006) and almost all patients recovered within a week to 10 days. A combination therapy with an effective safe analgesic and a true muscle relaxant for less than a week appears to be an excellent relief measure for acute back problems.

A double-blind comparison of flurbiprofen with diflunisal in the treatment of acute ankle sprains and strains

Fifty patients with acute ankle sprains/strains were treated with either 100 mg flurbiprofen or 500 mg diflunisal twice daily in a double-blind fashion for 18 days or until symptoms of the injury resolved. Tolerability of the drugs was evaluated by recording the occurrence of adverse drug reactions and monitoring laboratory parameters. Efficacy measurements were performed at enrollment and at Visit 2-Day 7, Visit 3-Day 14 and Visit 4-Day 21 to determine relief of symptoms and return to normal activities. Patients in both treatment groups exhibited marked improvement by Visit 2-Day 7 with almost complete recovery by Visit 3-Day 14. Flurbiprofen patients had a significantly shorter duration of therapy. Results from three of the six physician assessments were marginally to significantly superior for patients in the flurbiprofen group. The only reported adverse event was mild gastro-intestinal intolerance in a patient receiving diflunisal. Flurbiprofen and diflunisal appear to be effective and well-tolerated medications for the treatment of acute ankle sprains and strains.

Enhancement of the ocular hypotensive effect of acetazolamide by diflunisal

We studied the effect of diflunisal on intraocular pressure in patients with glaucoma who were receiving maximally tolerated therapy. Diflunisal therapy, 500 mg twice daily, was started in 48 patients for one week. No changes were made in their regular antiglaucoma medications. Intraocular pressure was reduced an additional 3.8 +/- 3.1 mm Hg (+/- S.D.) in the acetazolamide-treated patients (P less than .0001) and 1.6 +/- 1.5 mm Hg in methazolamide-treated patients (P less than .02), while no significant reduction in intraocular pressure was found in patients receiving topical medications alone. In 15 acetazolamide-treated patients, total plasma concentrations of acetazolamide after diflunisal therapy were significantly higher than the prediflunisal levels, suggesting a modest decrease in renal excretion. In seven acetazolamide-treated patients, free plasma concentrations of acetazolamide were found to increase 5.6-fold after diflunisal therapy. We concluded that diflunisal potentiated the ocular hypotensive effect of acetazolamide by increasing its free plasma level.

Evaluation of preoperative diflunisal for postoperative pain following periodontal surgery

The effectiveness of diflunisal as a preoperative medication to reduce pain following periodontal surgery was evaluated. Fifty patients were divided into two groups in a double-blind random manner: Group one received preoperative difunisal and Group two received preoperative placebo. The preoperative diflunisal group reported significantly less discomfort (P less than 0.05) than the preoperative placebo group and used rescue medication significantly less often (P less than 0.01). Therapeutic doses of diflunisal, given presurgically, are significantly more effective than placebo in limiting postoperative pain associated with periodontal surgery.

The pain intensity at analgesic intake, and the efficacy of diflunisal in single doses and effervescent acetaminophen in single and repeated doses

A double-blind, randomized analgesic trial was carried out in 150 patients undergoing surgical removal of their 2 impacted lower wisdom teeth. The analgesic efficacy of effervescent acetaminophen 500 or 1000 mg in a 2-dose regimen was compared with that of diflunisal 500 mg in a single dose. Each dose was taken when subjectively needed and the pain intensity was measured on a visual analog scale during the 10-hour period after first medication. The best pain reduction was achieved with diflunisal. The difference between diflunisal 500 mg and acetaminophen 1000 mg was significant, as was that between acetaminophen 1000 and 500 mg. The peak effect after the first dose occurred later but was greater with diflunisal than with acetaminophen. Patients needing analgesics at low pain intensities seemed to discriminate better between treatments, and the efficacy of acetaminophen was weakly dependent on the initial pain intensity. This intensity was difficult to predict, and only a poor correlation was found between the initial pain intensity and the patient's prior estimate of this.

A double-blind study of diflunisal and codeine compared with codeine or diflunisal alone in postoperative pain

A double-blind, randomized, parallel-group study compared the analgesic efficacy of a single oral dose of 500 mg diflunisal, 60 mg codeine, 500 mg diflunisal plus 60 mg codeine given as separate agents, and placebo in 161 patients with moderate to severe postoperative pain. Standard subjective measures were used to evaluate analgesia. Eight-hour sum of pain intensity differences and total pain relief scores for all active treatments were significantly better than were those for placebo (p less than 0.05). Diflunisal plus codeine performed the best followed by diflunisal, codeine, and placebo. Diflunisal plus codeine was better than placebo from 1 1/2 to 8 hours (p less than 0.01), better than codeine from 1 1/2 to 6 hours (p less than 0.05), and better than diflunisal alone from 1/2 to 1 1/2 hours (p less than 0.05) for most measures of analgesia. Factorial analysis demonstrated a significant early codeine effect and a significant diflunisal effect throughout. No significant treatment group differences were observed regarding adverse effects. Our data demonstrate that diflunisal plus codeine is generally well tolerated and provides analgesia superior to that of diflunisal or codeine alone in the treatment of moderate to severe postoperative pain.

Analgesic efficacy and tolerability of diflunisal in oral surgery

A double-blind, completely randomized study was carried out on 169 patients to compare the analgesic efficacy and tolerability of diflunisal with that of Veralgin after surgical removal of impacted third molars. One group received 1000 mg diflunisal (Donobid, MSD) 2 h preoperatively and then 500 mg twice daily for 2.5 days, and the other group Veralgin (aminophenazon. 286 mg, barbital. 114 mg, aethylmorph. hydrochlorid. 20 mg, Orion), a fixed combination widely used in Finland, 1 tablet twice daily beginning 2 h prior to operation. Visual analogue scales were used to estimate pain. Diflunisal was found to be superior in relieving pain in the early postoperative period, the associated frequency of adverse clinical experiences was lower and the final evaluation of analgesic efficacy by both the patients and the investigators, was in its favour. The study confirms that postoperative pain after third molar surgery can be controlled well without the use of mainly centrally acting combination analgesics.

[The uric acid-lowering effect of diflunisal]

20 patients with elevated serum uric acid levels and osteoarthritis of the hip or knee were given diflunisal 500 mg b.i.d. The joint complaints were influenced good to excellent in all patients. The uric acid levels were decreased from 7.37 to 6.22 mg/dl for the duration of this eight week open study. Diflunisal can be advocated also for the treatment of gout.

Paracetamol and diflunisal for pain relief following third molar surgery in Hong Kong Chinese

In a double blind study in Hong Kong Chinese, 250 mg of diflunisal, 500 mg of paracetamol or placebo were given for post-operative pain relief following 77 third molar surgical procedures. The intensity of pain was recorded on a visual analogue scale. The first and second doses of paracetamol reduced pain significantly more than placebo, while this was true only for the second dose of diflunisal. There was no significant difference in pain reduction with the first and second dose of paracetamol, when compared with the first and the second dose of diflunisal. In this study in Hong Kong Chinese, neither the dose nor the interval between ingestion of the analgesic tablets in patients, who needed analgesics for postoperative pain, were significantly different to that reported before in non-Chinese, in contrast to the popular belief that Chinese patients have higher pain thresholds. However, a higher proportion of Chinese than that reported in non-Chinese did not need any analgesics for relief of postoperative pain.

Evaluating the efficacy of a combination therapy

Standard multiple comparison techniques do not adequately address the situation in which one must demonstrate a combination therapy's superiority to both of its components. This paper proposes several alternative tests to deal with this situation, and evaluates the tests with a Monte Carlo sampling experiment that compares the actual with the nominal significance levels of the tests. Data from a clinical trial that compares the efficacy of a combination analgesic/muscle relaxant to its components and placebo in the treatment of low back pain and spasm illustrate the tests.