DECEMBER 27, 2024
LAS VEGAS—New retrospective claims data showed that the lidocaine topical system 1.8% patch (ZTlido, Scilex Pharmaceuticals) was associated with less use of opioid analgesics in patients with neuropathic pain compared with the 5% lidocaine patch.
Researchers led by Pain Medicine News editorial advisory board member Srinivas R. Nalamachu, MD, sought to determine the impact of the 1.8% and 5% lidocaine patches—each of which deliver equivalent doses of lidocaine—on opioid usage,
LAS VEGAS—New retrospective claims data showed that the lidocaine topical system 1.8% patch (ZTlido, Scilex Pharmaceuticals) was associated with less use of opioid analgesics in patients with neuropathic pain compared with the 5% lidocaine patch.
Researchers led by Pain Medicine News editorial advisory board member Srinivas R. Nalamachu, MD, sought to determine the impact of the 1.8% and 5% lidocaine patches—each of which deliver equivalent doses of lidocaine—on opioid usage, as measured by morphine milligram equivalents (MME) in patients with various neuropathic pain conditions. Although previous research demonstrated that treatment with a lidocaine patch can cut the use of opioids, this was the first head-to-head comparison of the two lidocaine patch formulations, according to Nalamachu.
The researchers looked at claims with a diagnosis of postherpetic neuralgia, diabetic peripheral neuropathy or low back pain (LBP) in the Optum Claims database from May 1, 2018, to Sept. 30, 2023. “Neuropathic pain treatment is complicated,” said Nalamachu, the founder and medical director of the Mid America PolyClinic, in Overland Park, Kan. “We don’t think of conditions like low back pain as neuropathic, but LBP has 50% contribution from the neuropathic side.”
Of patients meeting the study inclusion criteria, 343 were using the 1.8% patch, while 5,671 had been treated with the 5% patch.
More patients treated with the 1.8% patch saw either a decrease or discontinuation of opioid therapy compared with those treated with the 5% patch (51.9% vs. 45.5%). Of all study patients reporting a decrease in opioid use, significantly more in the 1.8% patch group experienced a 20% or greater reduction in MME, compared with those on 5% lidocaine therapy (21.3% vs. 13.4%; P=0.0008). Less patients treated with the 1.8% therapy increased their opioid dose after use of the patch (38.8% vs. 47.9%). No change in opioid use was reported by 9.3% of 1.8% patch patients and 6.6% of 5% patch patients.
What’s more, patients on the 1.8% patch had a non-significant change in their baseline MME (+3.1%; P=0.146), while those using the 5% patch experienced a significant increase in MME from baseline (+42.9%; P<0.001).
Nalamachu described the 1.8% patch as a “second-generation” product, noting that the composition and design allow for “significantly better adhesion compared to other formulations,” meeting more stringent FDA guidelines. Better pain treatment with a topical patch would thus allow for lower opioid utilization, according to Nalamachu, who added that the type of neuropathic pain treated was not a factor in the study.
“The No. 1 complaint [with topical lidocaine formulations] used to be that ‘it’s not sticking, it’s falling off,’” said Nalamachu, adding that poor adhesion can lead to a suboptimal dose of medication being given to the patient. “The question is often, ‘Why are we using a branded product when it is so costly compared to then non-branded product?’ So, we wanted to see the benefits [of using the branded medication].”
Nalamachu, who discussed the research in a presentation at the 2024 PAINWeek conference, added that it is often a challenge to get insurance companies to pay for new drugs. “When we prescribe a branded [medication], it’s a sign that we have tried other things and need a big gun,” Nalamachu said.
Limitations of the study, said Nalamachu, include that it is retrospective in design and utilizes data from a single claims company.
—Donald M. Pizzi
Nalamachu reported that he is a consultant to Scilex.
