Clinical benefit of transcutaneous afferent patterned stimulation (TAPS) in essential tremor patients with high unmet need: a secondary analysis of TAPS studies

ABSTRACT

Background

Transcutaneous afferent patterned stimulation (TAPS) is a noninvasive neuromodulation therapy that improves hand tremor in essential tremor (ET) patients. The benefits of TAPS in ET patients with high unmet need (severe tremor, non-responsive to medication, age ≥65 years) and early responders (substantial TAPS tremor improvement in the first month) remains unknown.

Research design and methods

Literature was surveyed for TAPS studies to assess the response in the high unmet need subgroup and early responders. Analyses were performed using previously collected Tremor Research Group Essential Tremor Rating Scale (TETRAS) scores, Bain & Findley activities of daily living (BF-ADL) scores, and tremor power.

Results

Significant differences in BF-ADL and TETRAS improvement were observed with TAPS over sham for the high unmet need subgroup in a randomized controlled study (P<0.03). During a 3-month open-label study, the high unmet need subgroup and early responders showed significant improvements in BF-ADL, TETRAS, and tremor power (P<0.001). Analysis of previous real-world evidence demonstrated that early responders maintained effectiveness and usage at 3 and 12 months (P<0.001).

Conclusions

TAPS showed comparable improvements in ET with high unmet need as reported in the original studies, and greater efficacy in early responders. These findings inform patient selection and the trial process for identifying TAPS responders.

KEYWORDS:

• Essential tremor
• peripheral neuromodulation
• secondary analysis
• transcutaneous afferent patterned stimulation
• high unmet need
• responder cohort

Declaration of interests

S Isaacson, R Pahwa and S Brillman are consultants of Cala Health. C Lu and A Kent are employees of Cala Health.

Reviewer disclosures

Peer reviewers on this manuscript have received an honorarium from Expert Review of Medical Devices for their review work but have no other relevant financial relationships to disclose.

Author contributions

SH Isaacson: Data interpretation, manuscript review and critique. R Pawah: Data interpretation, manuscript review and critique. S Brillman: Data interpretation, manuscript review and critique. C Lu: Study design, data analysis, manuscript drafting, review and critique. AR Kent: Study design, manuscript drafting, review and critique.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/17434440.2023.2274604

Additional information

Funding

This analysis was sponsored by Cala Health, Inc.