Efficacy of lacosamide in patients with diabetic neuropathy

To compare the effectiveness of lacosamide versus placebo in reducing neuropathic pain in patients with diabetic peripheral neuropathy.

Randomized, double-blind, placebo-controlled, parallel-group clinical trial

Conducted at the Department of Medicine, Nishtar Hospital Multan, after ethical approval. Patients enrolled consecutively, treated and followed for 12 weeks with 4-weekly assessments.

Inclusion Criteria: Age 20–60 years, either gender, Diabetes mellitus >5 years, VAS pain score >4, Informed consent given, Exclusion Criteria: Cardiovascular disease, Renal impairment or liver enzymes >2× normal, Pregnant or breastfeeding, Using other neuropathic pain medications (e.g., TCAs, lidocaine patch, mexiletine, tramadol, opioids, AEDs, NSAIDs)

Intervention group: Participants will receive Lacosamide (C13H18N2O3) tablets manufactured by Zakfas Pharmaceuticals Private Limited, orally. Dose will begin at 100 mg once daily, increased weekly by 100 mg to a maximum of 400 mg/day (200 mg twice daily) by week 4. This dose will be maintained for 12 weeks. Tablets will be provided in sealed identical packaging to ensure blinding. Follow-up will occur every 4 weeks. Control group: Participants will receive placebo tablets identical in appearance and schedule to the intervention group. Placebo will be manufactured by Zakfas Pharmaceuticals Privat Limited.Placebo contains inactive ingredients only and will be administered orally for 12 weeks using the same titration schedule to maintain blinding. Follow-ups will occur every 4 weeks.

Main Outcome Variable: Mean pain score after 12 weeks, measured using Visual Analogue Scale (VAS).

Participants will be randomized individually into two groups (Group A: Lacosamide, Group B: Placebo) using a simple randomization method. A computer-generated random number sequence will be prepared in advance using randomization software (e.g., www.randomizer.org). The sequence will be generated by a person not involved in participant enrollment. Allocation will be concealed using sequentially numbered, sealed, opaque envelopes (SNOSE) containing the group assignment. Each envelope will be opened only after the patient has been enrolled and consented. The envelopes will be identical and opaque to prevent selection bias, ensuring allocation concealment. This process guarantees that the assignment remains unpredictable and unbiased.

This will be a double-blinded study in which both the participants and the investigator assessing outcomes will be blinded to the treatment allocation. Lacosamide and placebo tablets will be identical in appearance, packaging, color, and size, and will be labeled with coded identifiers (e.g., A or B) by a third party not involved in participant recruitment or outcome assessment. The medication codes will be kept confidential and secured until the completion of data analysis. The investigator responsible for enrolling participants and recording outcomes will not have access to the allocation code. The blinding will be maintained throughout the study to minimize performance and assessment bias. Unblinding will only occur in case of medical emergency or serious adverse event where knowledge of the treatment is necessary for clinical decision-making.

Study Protocol (methods, randomization details). Statistical Analysis Plan (how data will be analyzed). Summary Results (aggregate data, no personal identifiers). De-identified Participant Data (only if ethically approved).

After publication of primary results, typically 6–12 months post-study completion. Data will be available for at least 5 years after publication.

Researchers; Healthcare providers .

Ethical & Confidentiality Considerations. De-identification: All participant data will be anonymized to prevent identification. Ethical Approval: Data sharing will comply with institutional IRB guidelines. Patient Consent: Informed consent forms will include a clause about potential data sharing.

Institutional Repository: Nishtar Medical University database (if available). Public Repositories: WHO ICTRP, ClinicalTrials.gov, Dryad, or Figshare. Journal Supplementary Files: If required by the journal where the study is published.

Researchers must submit a formal request via email to the principal investigator. Requests should include: Purpose of data use, Ethical approval (if applicable), Data security measures. Access will be granted only for non-commercial, research purposes.