The PATCH trial: efficacy and safety of 5% lidocaine-medicated plaster for the treatment of patients with trigeminal neuralgia: a study protocol for a multicentric, double-blind, enriched enrolment randomised withdrawal, vehicle-controlled study

The PATCH trial: 5% lidocaine-medicated plaster for trigeminal neuralgia-Results of a multicentric, enriched enrollment, randomized withdrawal, double-blind, vehicle-controlled, parallel-group study

OBJECTIVE

To explore the efficacy and safety of 5% lidocaine-medicated plaster (LMP) in patients with trigeminal neuralgia (TN).

BACKGROUND

TN is an excruciatingly painful type of neuropathic facial pain. Anti-epileptics are the first-line treatment for TN; however, these oral drugs alone sometimes fail to achieve satisfactory analgesic effects. Two retrospective studies have shown that LMP can be an effective and safe treatment option for some patients with TN. No other high-quality clinical studies have explored the effect and safety of LMP in patients with TN.

METHODS

The PATCH trial is an enriched enrollment with randomized withdrawal, double-blind, vehicle-controlled, parallel-group trial performed at five study centers. Eligible patients with TN received LMP during a 3-week initial open-label phase. Patients who met the response criteria entered the double-blind treatment phase and were randomly assigned for treatment with either LMP (LMP group) or vehicle patches (control group) at a 1:1 ratio. Patients who met the criteria for treatment failure were withdrawn from the double-blind treatment phase, and treatment was continued in the remaining patients for up to 28 days. The primary outcome was the number of treatment failures. The secondary endpoints were the time to loss of therapeutic response (LTR) in the double-blind phase and the weekly mean pain severity in both the open-label phase and the double-blind phase of the study.

RESULTS

The first patient was enrolled in this study on May 1, 2021, and the enrollment of the last patient was completed on August 26, 2022. A total of 307 patients were initially screened, 226 (74.0%) of whom entered the open-label phase. Of the 226 respondents, 124 (55.0%) were randomized to the double-blind phase. In the double-blind phase, 62 patients were assigned to the LMP group, and 62 were assigned to the control group. For the primary endpoint, 16 (26.0%) patients with LMP and 36 (58.0%) patients with vehicle patches met the treatment failure criteria during the double-blind phase (relative risk, 0.48; 95% confidence interval [CI], 0.31 to 0.75; p < 0.001). The survival curve of the LTR showed that the LTR of LMP was significantly longer than that of the vehicle patches (hazard ratio, 0.275; 95% CI, 0.15 to 0.50; log-rank p < 0.001). LMP also significantly reduced the weekly mean pain severity in the double-blind phase of the study (p = 0.007).

CONCLUSIONS

LMP produced partial relief of pain symptoms in some patients with TN. For responders, LMP may be used as an add-on therapy in a multidrug treatment protocol.

Challenges in Optimizing Nanoplatforms Used for Local and Systemic Delivery in the Oral Cavity

In this study, we focused on innovative approaches to improve drug administration in oral pathology, especially by transmucosal and transdermal pathways. These improvements refer to the type of microneedles used (proposing needles in the saw), to the use of certain enhancers such as essential oils (which, besides the amplifier action, also have intrinsic actions on oral health), to associations of active substances with synergistic action, as well as the use of copolymeric membranes, cemented directly on the tooth. We also propose a review of the principles of release at the level of the oral mucosa and of the main release systems used in oral pathology. Controlled failure systems applicable in oral pathology include the following: fast dissolving films, mucoadhesive tablets, hydrogels, intraoral mucoadhesive films, composite wafers, and smart drugs. The novelty elements brought by this paper refer to the possibilities of optimizing the localized drug delivery system in osteoarthritis of the temporomandibular joint, neuropathic pain, oral cancer, periodontitis, and pericoronitis, as well as in maintaining oral health. We would like to mention the possibility of incorporating natural products into the controlled failure systems used in oral pathology, paying special attention to essential oils.

Picornavirus infection enhances aspartate by the SLC38A8 transporter to promote viral replication

Foot-and-mouth disease, a class of animal diseases, is caused by foot-and-mouth disease virus (FMDV). The metabolic changes during FMDV infection remain unclear. Here, PK-15 cells, serum, and tonsils infected with FMDV were analyzed by metabolomics. A total of 284 metabolites in cells were significantly changed after FMDV infection, and most of them belong to amino acids and nucleotides. Further studies showed that FMDV infection significantly enhanced aspartate in vitro and in vivo. The amino acid transporter solute carrier family 38 member 8 (SLC38A8) was responsible for FMDV-upregulated aspartate. Enterovirus 71 (EV71) and Seneca Valley virus (SVV) infection also enhanced aspartate by SLC38A8. Aspartate aminotransferase activity was also elevated in FMDV-, EV71-, and SVV-infected cells, which may lead to reversible transition between the TCA cycle and amino acids synthesis. Aspartate and SLC38A8 were essential for FMDV, EV71, and SVV replication in cells. In addition, aspartate and SLC38A8 also promoted FMDV and EV71 replication in mice. Detailed analysis indicated that FMDV infection promoted the transfer of mTOR to lysosome to enhance interaction between mTOR and Rheb, and activated PI3K/AKT/TSC2/Rheb/mTOR/p70S6K1 pathway to promote viral replication. The mTORC1 signaling pathway was responsible for FMDV-induced SLC38A8 protein expression. For the first time, our data identified metabolic changes during FMDV infection. These data identified a novel mechanism used by FMDV to upregulate aspartate to promote viral replication and will provide new perspectives for developing new preventive strategies.