Utility of the heated lidocaine/tetracaine patch in the treatment of pain associated with shoulder impingement syndrome: a pilot study.

INTRODUCTION: Pain control is an important first step in the treatment of shoulder impingement syndrome (SIS) because fear of pain must be removed as an obstacle to participation in an appropriate physical therapy program. METHODS: Adult patients with SIS-associated pain of at least 2 weeks' duration and who had an average pain score of ≥4 on the zero- to ten-point Numeric Pain Rating Scale were eligible to enroll in this 2-week pilot study. Patients were treated with the heated lidocaine/tetracaine (70 mg/70 mg) patch (HLT patch) placed over the site of shoulder tenderness each morning and evening for a period of 2 to 4 hours. Average and worst pain during the previous 24 hours and shoulder range of motion were assessed at baseline and on Day 14. Results were expressed as change and percent change from baseline to Day 14. This pilot study was not powered for rigorous statistical analysis. RESULTS: Twenty patients (seven male, 13 female; average age 51.2 ± 10.8 years [mean ± standard deviation]) enrolled in this study, and 18 patients completed the protocol. The mean average pain score at baseline was 5.5 ± 1.1 (range 4 to 8). In the per-protocol population, average and worst pain scores declined by 2.4 ± 2.0 and 3.7 ± 2.7 points, respectively. Two-thirds of the patients demonstrated a clinically meaningful ≥30% decline in average pain score, and half of the patients demonstrated a ≥50% decline in average pain score. Shoulder internal rotation increased by 29.7° ± 21.8° and abduction increased by 40.0° ± 44.2°. Application-site erythema was reported by ten patients at some time during the study. CONCLUSION: Patients treated with the HLT patch for 14 days demonstrated clinically meaningful improvement in pain intensity and range of motion. Further controlled research is necessary to characterize the efficacy and tolerability of the HLT patch in the treatment of SIS.

Heated lidocaine/tetracaine patch for treatment of patellar tendinopathy pain.

INTRODUCTION: The pain of patellar tendinopathy (PT) may be mediated by neuronal glutamate and sodium channels. Lidocaine and tetracaine block both of these channels. This study tested the self-heated lidocaine-tetracaine patch (HLT patch) in patients with PT confirmed by physical examination to determine if the HLT patch might relieve pain and improve function. METHODS: Thirteen patients with PT pain of ≥14 days' duration and baseline average pain scores ≥4 (on a 0-10 scale) enrolled in and completed this prospective, single-center pilot study. Patients applied one HLT patch to the affected knee twice daily for 2-4 hours for a total of 14 days. Change in average pain intensity and interference (Victorian Institute of Sport Assessment [VISA]) scores from baseline to day 14 were assessed. No statistical inference testing was performed. RESULTS: Average pain scores declined from 5.5 ± 1.3 (mean ± standard deviation) at baseline to 3.8 ± 2.5 on day 14. Similarly, VISA scores improved from 45.2 ± 14.4 at baseline to 54.3 ± 24.5 on day 14. A clinically important reduction in pain score (≥30%) was demonstrated by 54% of patients. CONCLUSION: The results of this pilot study suggest that topical treatment that targets neuronal sodium and glutamate channels may be useful in the treatment of PT.

Effects of application durations and heat on the pharmacokinetic properties of drug delivered by a lidocaine/tetracaine patch: a randomized, open-label, controlled study in healthy volunteers.

BACKGROUND: The lidocaine/tetracaine heated patch is typically applied to the skin for 20 to 30 minutes to provide local dermal analgesia prior to venous access or minor dermatologic procedures. The potential exists for the use of multiple heated patches for longer application times, but the pharmacokinetic properties and tolerability of these multiple and/or longer applications have not been assessed. OBJECTIVE: The aim of this study was to assess the effects of heat and application time on the pharmacokinetic properties and tolerability of the patch after the application of 4 lidocaine/tetracaine (70/70 mg) heated patches applied at the same time in healthy volunteers for up to 12 hours. METHODS: In this randomized, open-labeled, controlled study, healthy subjects underwent 4 treatment periods (2-, 4-, or 12-hour application of 4 heated patches, or 4-hour application of 4 unheated patches), each separated by a 1-week washout period. RESULTS: Twelve subjects were enrolled (8 women, 4 men; mean age, 31.8 years; mean body mass index, 24.1 kg/m(2)). No tetracaine was detected in the plasma of any subject. Plasma concentrations of lidocaine increased rapidly during the first 2 hours of application in each heated-patch group, and with mean (SD) C(max) values of 18.2 (5.1), 25.7 (5.9), and 30.3 (8.1) ng/mL in the 2-, 4-, and 12-hour groups, respectively. Estimates of application time-normalized AUC(0-t) were not significantly different between the 2- and 4-hour applications of the heated patches, but were 25% lower during the 12-hour application time, suggesting continued but diminished drug delivery between 4 and 12 hours. Compared with subjects who received the unheated patch, those who received the heated patch had plasma lidocaine concentrations 5- and 3-fold higher after 30 and 60 minutes, respectively. Fifteen mild to moderate adverse events (AEs) were reported in 7 subjects, and none of the subjects discontinued the study due to treatment-related AEs. CONCLUSION: The heated patch continuously delivered drug for up to 12 hours and was generally well tolerated in these healthy subjects. ClinicalTrials.gov identifier: NCT01602757.

Effect of recombinant human parathyroid hormone (1-84) on vertebral fracture and bone mineral density in postmenopausal women with osteoporosis: a randomized trial.

BACKGROUND: Recombinant human parathyroid hormone (1-84) (PTH) increases bone mass and strength and improves bone quality by stimulating new bone formation. OBJECTIVE: To determine the safety of PTH and its effect on the incidence of vertebral fractures in postmenopausal women with osteoporosis. DESIGN: 18-month, randomized, double-blind, placebo-controlled, parallel-group study. SETTING: 168 centers in 9 countries. PATIENTS: 2532 postmenopausal women with low bone mineral density at the hip or lumbar spine. INTERVENTIONS: Women received 100 mug of recombinant human PTH or placebo daily by subcutaneous injection. All received calcium, 700 mg/d, and vitamin D3, 400 U/d. MEASUREMENTS: New or worsened vertebral fractures (primary outcome) and changes in bone mineral density and safety (secondary outcomes). RESULTS: 67.2% of patients who received at least 1 dose of the study drug completed the study. Parathyroid hormone reduced the risk for new or worsened vertebral fractures, but in sensitivity analyses, the magnitude of the reduction was changed with assumptions about fracture incidence in patients who did not complete the study (relative risk assuming no fractures, 0.42 [95% CI, 0.24 to 0.72] [P = 0.001]; relative risk assuming fracture incidence observed in all patients who completed the trial, 0.60 [CI, 0.36 to 1.00] [P = 0.05]; relative risk assuming fracture incidence observed in the placebo group, 0.62 [CI, 0.37 to 1.04] [P = 0.07]). Compared with placebo, mean bone mineral density increased at the spine by 6.9% (CI, 6.4% to 7.4%) and at the hip by 2.1% (CI, 1.7% to 2.5%) but decreased at the forearm in the PTH-treated group. Parathyroid hormone treatment increased the percentage of participants with hypercalciuria, hypercalcemia, and nausea by 24% (CI, 20% to 27%), 23% (CI, 21% to 26%), and 14% (CI, 11% to 16%), respectively, compared with placebo. LIMITATIONS: Baseline serum PTH and vitamin D levels were not measured. Many patients discontinued the trial prematurely. CONCLUSIONS: Parathyroid hormone (1-84) reduced the overall risk for new or worsened vertebral fracture in postmenopausal women with osteoporosis. Hypercalciuria, hypercalcemia, and nausea were more common in women who took the drug. Although the magnitude of the reduction was sensitive to assumptions about fracture incidence in patients who did not complete the study, the findings suggest that PTH provides an alternative therapeutic option for fracture prevention.

Defining a noncarcinogenic dose of recombinant human parathyroid hormone 1-84 in a 2-year study in Fischer 344 rats.

The carcinogenic potential of human parathyroid hormone 1-84 (PTH) was assessed by daily subcutaneous injection (0, 10, 50, 150 microg/kg/day) for 2 years in Fischer 344 rats. Histopathological analyses were conducted on the standard set of soft tissues, tissues with macroscopic abnormalities, selected bones, and bones with abnormalities identified radiographically. All PTH doses caused widespread osteosclerosis and significant, dose-dependent increases in femoral and vertebral bone mineral content and density. In the mid-and high-dose groups, proliferative changes in bone increased with dose. Osteosarcoma was the most common change, followed by focal osteoblast hyperplasia, osteoblastoma, osteoma and skeletal fibrosarcoma. The incidence of bone neoplasms was comparable in control and low-dose groups providing a noncarcinogenic dose for PTH of 10 microg/kg/day at a systemic exposure to PTH that is 4.6-fold higher than for a 100 microg dose in humans. The ability of PTH to interact with and balance the effects of both the PTH-1 receptor and the putative C-terminal PTH receptor, may lead to the lower carcinogenic potential observed with PTH than reported previously for teriparatide.