(330 days)
The Cala Trio device is indicated to aid in the temporary relief of hand tremors in the treated hand following stimulation in adults with essential tremor.
Cala Trio is a small, lightweight, wrist-worn stimulator device designed to aid in essential tremor symptom relief by applying Transcutaneous Afferent Patterned Stimulation (TAPS) to the median and radial nerves of a patient's wrist. The Cala Trio system includes three main components: (1) a rechargeable stimulator, (2) a wrist-worn electrode band, and (3) a base station that charges the device.
The stimulator component contains the electronics for delivering TAPS to the patient's wrist. There are three buttons on the stimulator that are used for calibration and stimulation amplitude adjustments, among other functions. Text prompts, stimulation delivery parameters, timer, and other messages are provided on the stimulator's full color display to provide instructions and stimulation delivery information.
To deliver therapy, the stimulator is attached to the wrist band, which includes integrated electrodes placed at appropriate intervals around the inner diameter of the band to properly target the median and radial nerves. To accommodate a broad distribution of wrist sizes, the band is available in three sizes (small, medium, and large). Each band size is also available in right or left-handed versions to target the appropriate nerves of the prescribed hand.
The provided text describes a 510(k) premarket notification for a medical device called Cala Trio. This submission focuses on demonstrating substantial equivalence to a previously cleared predicate device, Cala ONE, rather than establishing de novo performance criteria for an entirely new device. Therefore, the "acceptance criteria" discussed are primarily about demonstrating that the modified device (Cala Trio) is as safe and effective as the predicate device (Cala ONE), despite some changes.
Here's an analysis of the provided information concerning the "acceptance criteria" and the study that proves the device meets them, structured according to your request:
1. Table of Acceptance Criteria and Reported Device Performance
Since this is a substantial equivalence submission, the "acceptance criteria" are not absolute performance targets set for a new device type, but rather the demonstration that the Cala Trio performs equivalently to the Cala ONE. The performance here is primarily about achieving similar clinical outcomes and meeting non-clinical safety/electrical standards.
| Acceptance Criteria (Demonstrated Equivalence to Predicate) | Reported Device Performance (Cala Trio) |
|---|---|
| Clinical Equivalence: | |
| Continued temporary relief of hand tremors in ET. | Study 1 (Isaacson et al., 2020 - home-use): 64% of 205 patients (completing the study) self-reported persistent tremor relief after 40 minutes of stimulation, lasting on average 94 minutes (median 60 minutes). This study also showed: 62% (TETRAS) and 68% (BF-ADL) of 'severe' or 'moderate' patients improved to 'mild' or 'slight'. Clinicians (CGI-I) reported improvement in 68% of patients, and 60% (PGI-I) of patients reported improvement. QUEST also improved. These results were stated to be "consistent with the original clinical study supporting the granting of DEN170028 for the Cala ONE." Study 2 (Yu et al., 2020 - single session): 70-80% of TAPS users demonstrated tremor relief for 60 minutes after stimulation in a study of 15 participants. |
| Non-clinical & Technical Equivalence: | |
| Biocompatibility in accordance with ISO 10993-1. | Demonstrated Biocompatibility in accordance with ISO 10993-1:2018 (Cala ONE was 2009 version). |
| Meets IEC60601-1 and collateral standards (EMC & Electrical Safety). | Meets all requirements of IEC60601-1 and relevant collateral and particular standards. |
| Stimulation waveform conforms to internal standard. | Stimulation waveform conforms to requirements of internal standard test method and acceptance criteria. |
| Electrode performance and shelf life. | Electrode performance conforms to requirements of internal standard test method and acceptance criteria at T=24 months. |
| Sensor performance and associated algorithms. | Non-clinical performance testing demonstrated that the measurements obtained from the Cala Trio sensor (triaxial accelerometer only) are equivalent to those obtained from the Cala ONE sensors (gyroscope and triaxial accelerometer). |
| Electrical stimulation characterization. | The therapy pattern parameters are unchanged, and clinical evidence demonstrates that changes in maximum output voltage, maximum output current, maximum phase charge, maximum current density, maximum average current, and maximum average power density do not impact safety or effectiveness of the device. The functionality of the output channel and therapy parameters are unchanged despite going from 1 channel with 2 alternating outputs to 2 alternating channels. |
2. Sample Sizes Used for the Test Set and Data Provenance
- Isaacson et al. (2020) Study:
- Sample Size: 263 enrolled subjects, with 205 subjects completing the study.
- Data Provenance: Not explicitly stated, but described as a "prospective, multi-center, single-arm three months study of repeated home use." Given the authors and typical clinical trial landscapes for such devices, it's highly likely to be US-based, and it is prospective.
- Yu et al. (2020) Study:
- Sample Size: 15 participants.
- Data Provenance: Described as "an in-office, single session study." Not explicitly stated, but likely also prospective and US-based given the authors.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not describe the establishment of a "ground truth" by experts in the way it might for an AI image analysis device (e.g., radiologists labeling images). Instead, the performance is assessed via:
- Patient self-reported outcomes: PGI-I (Patient Global Impression of Improvement).
- Clinician-reported outcomes: CGI-I (Clinical Global Impression of Improvement).
- Standardized tremor assessment scales: TETRAS (The Essential Tremor Rating Assessment Scale) and BF-ADL (Bain and Findley Activities of Daily Living Scale).
- QUEST (Quality of Life in Essential Tremor) scale.
For the clinician-reported outcomes, while not specified, it's presumed that the clinicians involved in the multi-center study were qualified medical professionals, likely neurologists or specialists in movement disorders, who are trained to assess these scales. The number of such "experts" would correspond to the number of clinicians participating in the study who performed these assessments. The document does not specify the exact number of clinicians or their precise qualifications beyond what is implied by their role in a clinical study for essential tremor.
4. Adjudication Method for the Test Set
No explicit adjudication method (like 2+1 or 3+1 consensus) is described for the clinical outcome measures. These measures (TETRAS, BF-ADL, CGI-I, PGI-I, QUEST) are often collected directly by study staff, clinicians, or patients, and then analyzed statistically. It is not an image review or labeling task that typically requires adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done, If so, What was the Effect Size of How Much Human Readers Improve with AI vs Without AI Assistance
No MRMC study was performed or is relevant here, as this device (Cala Trio) is a therapeutic device for tremor relief, not an AI diagnostic imaging tool interacting with human readers.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done
The Cala Trio is a physical therapeutic device. Its core function is to deliver transcutaneous afferent patterned stimulation (TAPS). Its performance is inherently "standalone" in the sense that the device itself delivers the therapy. There is no human-in-the-loop performance being evaluated in the context of an algorithm's output needing interpretation by a human. The patient uses the device, but the device's therapeutic action is direct.
7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.)
The "ground truth" in this context refers to the assessment of tremor relief and improvement in daily living and quality of life. This was established using:
- Clinical Assessment Scales: TETRAS, BF-ADL (Likely assessed by clinicians).
- Patient-Reported Outcomes: PGI-I, QUEST (Self-reported by patients).
- Clinician Global Impression of Improvement: CGI-I (Assessed by clinicians).
- Self-reported duration of tremor relief from patients.
This is a combination of subjective patient feedback and objective (clinical scale scores) assessments.
8. The Sample Size for the Training Set
This document describes a 510(k) submission for a device modification, relying on clinical evidence of its direct predecessor (Cala ONE) and clinical studies of the modified device (Cala Trio) for substantial equivalence. It does not refer to a machine learning context where a separate "training set" would be used to develop an algorithm for diagnosis or image analysis. The "training" for the device's therapeutic protocol was established in prior research for the Cala ONE and maintained for the Cala Trio.
9. How the Ground Truth for the Training Set was Established
As above, this context is not applicable. The device's therapeutic mechanism (TAPS) is based on established neurophysiological principles, not on a machine learning model trained on a dataset with a defined "ground truth" in the AI sense. The clinical studies establish the device's effectiveness, not a training ground truth for an algorithm.
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October 5, 2021
Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.
Cala Health, Inc. Danielle Boyd Director, Regulatory Affairs 875 Mahler Road, Suite 168 Burlingame, California 94010
Re: K203288
Trade/Device Name: Cala Trio Regulation Number: 21 CFR 882.5897 Regulation Name: External upper limb tremor stimulator Regulatory Class: Class II Product Code: QBC Dated: November 6, 2020 Received: November 9, 2020
Dear Danielle Boyd:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part
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801); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Patrick Antkowiak Acting Assistant Director DHT5B: Division of Neuromodulation and Physical Medicine Devices OHT5: Office of Neurological and Physical Medicine Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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Indications for Use
510(k) Number (if known) K182706
Device Name Cala Trio
Indications for Use (Describe)
The Cala Trio device is indicated to aid in the temporary relief of hand tremors in the treated hand following stimulation in adults with essential tremor.
| Type of Use (Select one or both, as applicable) | |
|---|---|
| ------------------------------------------------- | -- |
X Prescription Use (Part 21 CFR 801 Subpart D)
| Over-The-Counter Use (21 CFR 801 Subpart C)
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510(k) Summary 510(k): Device Modification [K203288]
- I. Submitter Manufacturer: Cala Health, Inc. 875 Mahler Rd, Suite 168 Burlingame, CA 94010 Phone: (415) 890-3961 Fax: None Primary Contact: Danielle McDonnell Boyd Director, Regulatory Affairs, Cala Health danielle(@calahealth.com (415) 819-2935 Date Prepared: October 4, 2021 II. Subiect Device Cala Trio™ Trade Name: Classification Name: External upper limb tremor stimulator Device Classification: Class II Regulation: 21 CFR 882.5897 Product Code: QBC III. Predicate Device Predicate Device: Cala ONE DEN170028, K182706 Prior Submissions: Indications for Use: Cala ONE is indicated to aid in the transient relief of hand tremors in the treated hand following stimulation in
adults with essential tremor.
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IV. Description of Device
Cala Trio is a small, lightweight, wrist-worn stimulator device designed to aid in essential tremor symptom relief by applying Transcutaneous Afferent Patterned Stimulation (TAPS) to the median and radial nerves of a patient's wrist. The Cala Trio system includes three main components: (1) a rechargeable stimulator, (2) a wrist-worn electrode band, and (3) a base station that charges the device.
The stimulator component contains the electronics for delivering TAPS to the patient's wrist. There are three buttons on the stimulator that are used for calibration and stimulation amplitude adjustments, among other functions. Text prompts, stimulation delivery parameters, timer, and other messages are provided on the stimulator's full color display to provide instructions and stimulation delivery information.
To deliver therapy, the stimulator is attached to the wrist band, which includes integrated electrodes placed at appropriate intervals around the inner diameter of the band to properly target the median and radial nerves. To accommodate a broad distribution of wrist sizes, the band is available in three sizes (small, medium, and large). Each band size is also available in right or left-handed versions to target the appropriate nerves of the prescribed hand.
V. Indications for Use
Cala Trio is indicated to aid in the temporary relief of hand tremors in the treated hand following stimulation in adults with essential tremor.
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VI. Technological Characteristics
The following table provides a summary comparison for technical characteristics between Cala ONE (predicate device) and Cala Trio (subject device).
| Cala ONEDEN170028K182706(Predicate Device) | Cala TrioK203288(Subject Device) | Discussion ofDifferences | |
|---|---|---|---|
| Intended Use | Delivery of transcutaneousafferent patternedstimulation (TAPS) forhand tremors in essentialtremor patients | Delivery of transcutaneousafferent patternedstimulation (TAPS) forhand tremors in essentialtremor patients | Same |
| Indicationsfor Use | Cala ONE is indicated toaid in the transient relief ofhand tremors in adults withessential tremor. | Cala Trio is indicated toaid in the temporary reliefof hand tremors in adultswith essential tremor. | Substantially EquivalentThe indications for useis changed from"transient" to"temporary” but doesnot impact safety oreffectiveness. Cala Triois indicated for the samecondition and patientpopulation.Clinical evidencesummarized in SectionVII demonstrates thatthe indications for usechange does not impactthe safety oreffectiveness of thedevice. |
| Cala ONEDEN170028K182706(Predicate Device) | Cala TrioK203288(Subject Device) | Discussion ofDifferences | |
| Design | Stimulator with on- boardmotion sensorspermanently mounted onwristband | Stimulator with on- boardmotion sensors that isdetachable from wristband | Substantially EquivalentThe difference incomponent attachmentdoes not impact thesafety or effectiveness ofthe device.The TAPS therapyparameters ascontrolled by Cala Trioare unchanged fromCala ONE. |
| Wrist-worn band with three4x4 cm² electrodesmanually attached by theuser | Wrist-worn band with three4.84 cm² electrodesembedded in the band | Substantially EquivalentThe difference inelectrode configurationdoes not impact thesafety or effectiveness ofthe device.Clinical evidencesummarized in SectionVII demonstrates thatthe surface area changedoes not impact thesafety or effectiveness ofthe device.The Cala Trio electrodesurface area isequivalent and theelectrode material areunchanged from Cala | |
| Cala ONEDEN170028K182706 | Cala TrioK203288 | Discussion ofDifferences | |
| (Predicate Device) | (Subject Device) | ||
| AC-powered charger thatconnects to the stimulatorvia USB port | AC-powered base stationfor recharging thestimulatorBase Station includes anLTE antenna that providesconnection and datatransfer to cloud systemwhich supports deviceoperations such as deviceassistance and maintenance | Substantially EquivalentThe difference in thecharging componentdoes not impact thesafety or effectiveness ofthe device.The Cala Trio energysource (battery) andstimulator circuitry isunchanged from CalaONE.The cloud providessupport and maintenancefunctions only.Transferred data is usedfor monitoringpurposes only and is notused for diagnosis orother treatment-relatedrecommendations ortreatment adjustments. | |
| Embedded firmwarecontrol of devicecalibration, stimulationdelivery, and devicefunction | Embedded firmwarecontrol of devicecalibration, stimulationdelivery, and devicefunction | Same | |
| Cala ONEDEN170028K182706(Predicate Device) | Cala TrioK203288(Subject Device) | Discussion ofDifferences | |
| Device sensors (gyroscopeand triaxial accelerometer)measure tremor motion | Device sensors (triaxialaccelerometer) measuretremor motion | Substantially EquivalentThe difference in themotion sensors does notimpact safety oreffectiveness.Non-clinicalperformance testingdemonstrated that themeasurements obtainedfrom the Cala Triosensor are equivalent tothose obtained from theCala ONE sensors. | |
| Features | • Set-up calibration• Stimulation intensitycontrol• Therapy available ondemand | • Set-up calibration• Stimulation intensitycontrol• Therapy available ondemand | Same |
| UserInterface | Stimulator displayguides device setup,operation, and usageinformation.Four buttons on the devicehousing allowuser control of thestimulation amplitude anddevice calibration | Stimulator displayguides device setup,operation, and usageinformation.Three buttons on thedevice housing allowuser control of thestimulation amplitude anddevice calibration | Substantially EquivalentThe difference in theuser interface does notimpact safety oreffectiveness.The Cala Trio buttonsserve the same combinedfunctions as thosecontrolled separately bythe buttons in CalaONE. The device setup,operation, and usageinformation areunchanged. |
| Prescriptionor OTC | Prescription | Prescription | Same |
| Sterility | Non-sterile | Non-sterile | Same |
| Materials | Biocompatible wrist band | Biocompatible wrist band | Same |
| Cala ONEDEN170028K182706(Predicate Device) | Cala TrioK203288(Subject Device) | Discussion ofDifferences | |
| Energy Source | Permanent 3.7V Lithium-Ion rechargeablebattery | Permanent 3.8V Lithium-Ion rechargeablebattery | Substantially EquivalentThe difference in batteryvoltage does not impactsafety or effectiveness.The Cala Trio and CalaONE device batteriesboth comply with IEC62133 standard. |
| Frequencyof Use | The device is used asneeded by the patient | The device is used asneeded by the patient | Same |
| Band Use Life | Single Use (DEN170028)30 Days (K182706) | 90 Days | Substantially EquivalentThe difference in banduse-life does not impactsafety or effectiveness.Non-clinicalperformance testingdemonstrated that theCala Trio electrodemaintains electrodeintegrity and deliverstherapy as intended forthe duration of the 90-day use-life. |
| Principle ofOperations | Biphasic Waveform,rectangular | Biphasic Waveform,rectangular | Same |
| Output Modes | 1 channel with 2alternating outputs | 2 alternating channels | Substantially EquivalentThe difference in thenumber of outputchannels does notimpact safety oreffectiveness.The functionality of theoutput channel and thetherapy parameters areunchanged. |
| Cala ONEDEN170028K182706(Predicate Device) | Cala TrioK203288(Subject Device) | Discussion ofDifferences | |
| Output | Current Regulated | Current Regulated | Same |
| HousingMaterials | PlasticVelcro Straps (Nylon) | PlasticVelcro Straps (Nylon) | Same |
| Weight | 56g | Stimulator: 28gBase Station: 209gBand: 13.4g - 15.9g | Substantially EquivalentThe difference in deviceweight does not impactsafety or effectiveness.The total weight of thepatient-worncomponents of CalaTrio and Cala ONE(band and stimulator)have equivalent weights. |
| Dimensions(mm) | 52 x 79 x 16 | Stimulator: 42 x 55 x 13Base Station: 104 x 36 x 91Band Length: 252.5 - 327.5Band Width: 20.8 -54.1 | Substantially EquivalentThe difference in devicedimensions does notimpact safety oreffectiveness.The patient-worncomponents) of CalaTrio and Cala ONE(band and stimulator)have equivalentdimensions |
| OutputSpecificationCategory | Cala ONEDEN170028K182706(Predicate Device) | Cala TrioK203288(Subject Device) | Comparison Result |
| Waveform | Biphasic | Biphasic | Same |
| Shape | Rectangular | Rectangular | Same |
| MaximumOutput Voltage(volts) | 7.5 @ 500Ω | 7.5 @ 500Ω | Same |
| 120 @ 10kΩ | 80 @ 10kΩ | SubstantiallyEquivalentThe therapy patternparameters areunchanged.Clinical evidencesummarized in SectionVII demonstrates thatthe reduction inmaximum outputvoltage does notimpact safety oreffectiveness of thedevice | |
| Maximum OutputCurrent (mA) | 15 @ 500Ω | 8 @ 500Ω | SubstantiallyEquivalentThe therapy patternparameters areunchanged. |
| 12 @ 10kΩ | 8 @ 10kΩ | Clinical evidencesummarized in SectionVII demonstrates thatthe reduction inmaximum outputcurrent does notimpact safety oreffectiveness of thedevice | |
| OutputSpecificationCategory | Cala ONEDEN170028K182706(Predicate Device) | Cala TrioK203288(Subject Device) | Comparison Result |
| Duration ofprimary(depolarizing)phase(µsec) | 300 | 300 | Same |
| Pulse Duration(µsec) | 650 | 650 | Same |
| Frequency (Hz) | 150 | 150 | Same |
| Symmetricalphases? | Yes | Yes | Same |
| Phase Duration(µS) | 300each phase | 300each phase | Same |
| Net Charge(µC) | 0 @500Ω | 0 @500Ω | Same |
| MaximumPhase Charge(µC) | 4.5 @ 500Ω | 2.4 @ 500Ω | SubstantiallyEquivalentThe therapy patternparameters areunchanged.Clinical evidencesummarized inSection VIIdemonstrates thatthe reduction inmaximum phasecharge does notimpact safety oreffectiveness of thedevice |
| OutputSpecificationCategory | Cala ONEDEN170028K182706(Predicate Device) | Cala TrioK203288(Subject Device) | Comparison Result |
| MaximumCurrent Density(mA/cm², r.m.s.) | 2.41 @ 500Ω | 1.17 @ 500Ω | SubstantiallyEquivalentThe therapy patternparameters areunchanged.Clinical evidencesummarized in SectionVII demonstrates thatthe reduction inmaximum currentdensity does notimpact safety oreffectiveness of thedevice |
| MaximumAverage Current(mA) (averageabsolute value) | 1.35 @ 500Ω | 0.72 @ 500Ω | SubstantiallyEquivalentThe therapy patternparameters areunchanged.Clinical evidencesummarized in SectionVII demonstrates thatthe reduction inmaximum averagecurrent does notimpact safety oreffectiveness of thedevice |
| OutputSpecificationCategory | Cala ONEDEN170028K182706 | Cala TrioK203288 | Comparison Result |
| (Predicate Device) | (Subject Device) | ||
| MaximumAverage PowerDensity(mW/cm²) | 2.30 @ 500Ω | 1.12 @ 500Ω | SubstantiallyEquivalent |
| The therapy patternparameters areunchanged. | |||
| Clinical evidencesummarized in SectionVII demonstrates thatthe reduction inmaximum averagepower density does notimpact safety oreffectiveness of thedevice |
Technical Comparison of the Subject Device and Predicate Device
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VII. Performance and Non-Clinical Testing
The following tables provide a summary comparison for performance, and nonclinical testing of Cala ONE (predicate device) and Cala Trio (subject device).
Performance Comparison of the Modified Device and Predicate Device
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Nonclinical Testing Comparison of the Modified Device and Predicate Device
| OutputSpecificationCategory | Cala ONE | Cala Trio | Comparison Result |
|---|---|---|---|
| DEN170028K182706(Predicate Device) | K203288(Subject Device) | ||
| Biocompatibility | DemonstratedBiocompatibilityin accordance withISO 10993-1:2009 | DemonstratedBiocompatibility inaccordance withISO 10993-1:2018 | Same |
| EMC andElectricalSafety | Meets all requirementsof IEC60601-1 andrelevant collateral andparticular standards | Meets all requirementsof IEC60601-1 andrelevant collateral andparticular standards | Same |
| StimulationWaveformTesting | Stimulation waveformconforms torequirements ofinternal standard testmethod and acceptancecriteria | Stimulation waveformconforms torequirements of internalstandard test method andacceptance criteria | Same |
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| OutputSpecificationCategory | Cala ONEDEN170028K182706 | Cala TrioK203288 | Comparison Result |
|---|---|---|---|
| (Predicate Device) | (Subject Device) | ||
| Shelf LifeTesting | Electrode performanceconforms torequirements ofinternal standard testmethod and acceptancecriteria at T=24 months | Electrode performanceconforms torequirements of internalstandard test method andacceptance criteria atT=24 months | Same |
Clinical VIII.
The following clinical evidence was used to support the change in the indications for use:
- . In an end-of-study survey following three months of repeated home use in Essential Tremor (ET) patients, 64% of the 205 patients who completed the study self-reported persistent tremor relief after the 40 minutes of stimulation lasting on average 94 minutes (standard deviation = 138; median = 60). (Isaacson, S. H. et al. (2020) "Prospective home-use study on noninvasive neuromodulation therapy for Essential Tremor," Tremor Other Hyperkinet. Mov., 10(1): 29. pp.-6 | doi: 10.5334/tohm.59).
- . A study on 15 participants with ET who completed an in-office, single session study that measured tremor relief during stimulation, immediately after stimulation, and up to an hour after the end of stimulation demonstrated tremor relief after stimulation for 60 minutes for 70-80% of TAPS users (Yu. J. et al. (2020). "Transcutaneous afferent patterned stimulation therapy reduces hand tremor for one hour in essential tremor patients," Front. Neurosci., Vol. 14, pp. 1- 9 | doi: 10.3389/fnins.2020.530300)
The following clinical evidence was used to support the change in electrode surface area and reduction in output stimulation intensity:
- . A prospective, multi-center, single-arm three months study of repeated home use of the Cala TRIO device (263 enrolled subjects with 205 subjects completing the study) in ET patients demonstrated results consistent with the original clinical study supporting the granting of DEN170028 for the Cala ONE. Results demonstrated that 62% (TETRAS) and 68% (BF-ADL) of 'severe' or 'moderate' patients improved to 'mild' or 'slight'. Clinicians (CGI-I) reported improvement in 68% of patients, 60% (PGI-I) of patients reported improvement, and QUEST improved. (Isaacson, S. H. et al. (2020) "Prospective home-use study on noninvasive neuromodulation therapy for Essential Tremor." Tremor Other Hyperkinet. Mov., 10(1): 29, pp.-6 | doi: 10.5334/tohm.59).
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IX. Substantial Equivalence
Substantial equivalence of Cala Trio to Cala ONE is demonstrated based on the comparison of technical characteristics, performance, and clinical and nonclinical testing. In summary:
- . The intended use is unchanged but the indications for use has changed and has been supported by clinical data as described above.,
- . Cala has provided the following evidence to demonstrate that any differences in labeling, technological characteristics, or materials do not impact safety or effectiveness (see Sections VII and VII above for additional detail):
- The Cala Trio labeling contains all content per the Special Controls identified for external limb tremor stimulators per 21 CFR 882.5897
- Clinical performance testing as described in Section VIII above -
- Non-clinical performance testing confirmed the following: -
- Electrical stimulation characterization .
- . Electrode impedance testing and shelf-life
- . Sensor performance and associated algorithms
- Biocompatibility testing demonstrates that both Cala ONE and Cala Trio meet the ISO 10993-1 standard and are therefore substantially equivalent with respect to biocompatibility.
- EMC and Electrical Safety testing demonstrates that Cala ONE and Cala Trio are ● compliant with the same applicable IEC 60601 clauses and are substantially equivalent with respect to Electrical Safety and EMC considerations.
- Stimulation waveform testing demonstrates that Cala ONE and Cala Trio produce a stimulation output that meets the same internal testing and acceptance criteria and are substantially equivalent with respect to stimulation output.
- . Real time aging and performance testing of Electrodes demonstrate that both Cala ONE and Cala Trio bands meet the same performance requirements at 24 months and are substantially equivalent with respect to shelf life.
X. Conclusion
In summary, Cala ONE and Cala Trio are substantially equivalent. Cala has provided evidence as described above to demonstrate that any differences in the indications for use and technological characteristics do not impact safety or effectiveness.
§ 882.5897 External upper limb tremor stimulator.
(a)
Identification. An external upper limb tremor stimulator is a prescription device which is placed externally on the upper limb and designed to aid in tremor symptom relief of the upper limb.(b)
Classification. Class II (special controls). The special controls for this device are:(1) Non-clinical performance testing must assess the following:
(i) Characterization of the electrical stimulation, including the following, must be performed: Waveforms, output modes, maximum output voltage, maximum output current, pulse duration, frequency, net charge per pulse, maximum phase charge at 500 ohms, maximum current density, maximum average current, and maximum average power density.
(ii) Impedance testing, current distribution across the electrode surface area, adhesive integrity, and shelf life testing of the electrodes and gels must be conducted.
(iii) Simulated use testing of sensor performance and the associated algorithms that determine the stimulation output must be conducted.
(2) Patient-contacting components of the device must be demonstrated to be biocompatible.
(3) Performance testing must demonstrate electrical, thermal, and mechanical safety along with electromagnetic compatibility (EMC) of the device in the intended use environment.
(4) Software verification, validation, and hazard analysis must be performed.
(5) Physician and patient labeling must include:
(i) Summaries of electrical stimulation parameters;
(ii) Instructions on how to correctly use and maintain the device;
(iii) Instructions and explanations of all user-interface components;
(iv) Instructions on how to clean the device;
(v) A shelf life for the electrodes and gel; and
(vi) Reuse information.