Transit-Pellets is intended to be used for evaluation of colonic transit time in patients with chronic constipation and used to aid in differentiating slow and normal transit constipation. Ten (10) radiopaque markers per day are swallowed for six consecutive days. On day seven an abdominal radiograph is taken. Based on the number of retained markers and the position in colon a colonic transit time is calculated and compared to reference values. Both total transit and segmental transit dysfunction in the colon can be evaluated with the device. By dividing the particle dose on day six by taking five (5) markers in the morning and five (5) markers in the evening, the whole range of transit times (slow, normal, rapid) transit can be measured from the radiograph.

Transit-Pellets is a convenience package of radiopaque markers (22% Barium Sulphate, 78% Elastosil® R 401/60 Silicone rubber) placed in veqetarian capsules from cellulose (HPMC, Hydroxypropyl-methylcellulose), intended for single patient use. The dimension of the markers is 2x4.5mm (ring-formed markers) and 6x2mm (tube-formed markers). The capsules are packed in a blister pack and the blister pack is placed inside a folding box.

AI/ML Overview

The provided text describes a 510(k) premarket notification for the "Transit-Pellets" device, which is a gastrointestinal motility monitoring system. This document is a clearance letter from the FDA, asserting substantial equivalence to a predicate device, rather than a detailed study report for a novel AI device requiring extensive performance metrics against acceptance criteria.

Therefore, much of the requested information (acceptance criteria for AI, sample size for test sets/training sets, number of experts for ground truth, adjudication methods, MRMC studies, standalone AI performance, etc.) is not applicable to this specific device and submission type, as it is a physical medical device (radiopaque markers) and not an AI/ML software. The crucial point is that no AI component is described or evaluated in this document.

However, I can extract and present the information relevant to a traditional medical device's performance and equivalence.

Device Name: Transit-Pellets
Regulation Name: Gastrointestinal Motility Monitoring System
Regulatory Class: Class II
Product Code: FFX
Indications for Use: For evaluation of colonic transit in adult patients with chronic constipation and used to aid in differentiating slow and normal constipation.

1. A table of acceptance criteria and the reported device performance

The document does not explicitly state "acceptance criteria" in a quantitative, measurable table as one would for an AI model's performance (e.g., AUC > X, sensitivity > Y%). Instead, the device's performance is demonstrated through comparisons to a predicate device and safety/material testing, confirming it performs "as intended" and is "safe and effective."

Characteristic/Criterion	Predicate Device (Sitzmarks)	Applicant Device (Transit-Pellets)	Substantial Equivalence (SE) Declared	Explanation of Performance / Meeting Criterion
Intended Use	For evaluation of colonic transit in patients with chronic constipation and used to aid in differentiating slow and normal constipation.	For evaluation of colonic transit in patients with chronic constipation and used to aid in differentiating slow and normal constipation.	X	Identical wording for intended use.
Application	Measuring and using colonic transit time to evaluate patients with chronic (severe) constipation.	Measuring and using colonic transit time to evaluate patients with chronic (severe) constipation.	X	Identical application described.
Target Population	Adult patients with chronic (severe) constipation.	Adult patients with chronic (severe) constipation.	X	Identical target population.
Anatomical Site	Gastrointestinal tract/colon	Gastrointestinal tract/colon	X	Identical anatomical site.
Where Used	Hospitals, clinics	Hospitals, clinics	X	Identical use environments.
Design	Three different shapes: O Rings, Double D, Tri-Chamber.	Ring-formed and tube-formed markers.	X	Different shapes but considered substantially equivalent as studies showed transit through colon was identical for ring-formed, tube-formed and cube-formed markers.
Dimensions	1mm x 4.5mm	2 x 4.5mm, 6 x 2mm	X	Different dimensions but considered equivalent; device claims sizes <8mm ensure proper gastric emptying and transit.
Materials	Markers: Polyvinylchloride, Barium sulphate, etc. Capsules: Hypromellosa.	Markers: Barium sulphate, Elastosil® R 401/60 Silicone rubber. Capsules: HPMC, Hydroxypropyl-methylcellulose.	X	Different materials but demonstrated to be biocompatible and radiopaque, fulfilling the functional requirements. The product also described using vegetative capsules (vs gelatine) which would make it an improvement.
Principle of Operation	Patient swallows fixed dose radiopaque marker for days. Abdominal radiograph(s) taken. Number/position of markers used to calculate colonic transit time.	Patient swallows fixed dose radiopaque marker for days. On day 7, single abdominal radiograph or fluoroscopy taken. Number/position of markers used to calculate colonic transit time.	X	Fundamentally the same principle. Differences in number of radiographs "may be necessary" for predicate vs. "single abdominal radiograph" for applicant are noted, but overall concept is identical.
Performance (Measurement)	Colonic Transit Time (CTT/OATT) numerical values reported in hours.	Colonic Transit Time (CTT/OATT) numerical values reported in days. ASTM F640-12 RO confirmed.	X	Difference in units (hours vs. days) but both measure the same physiological process. Applicant device has confirmed radiopacity standard.
Biocompatibility	No information	Yes, safe for intended use (ISO 10993-5, -10, -11). Confirmed non-cytotoxic, non-irritant, non-sensitizing, non-pyrogenic, no systemic toxicity.	Not directly comparable for acceptance, but demonstrates safety of new device.	The device passed biocompatibility testing as per ISO 10993 standards.
Radiopacity	Not explicitly stated but inherent for its function.	Confirmed by ASTM F640-12.	(Implied for predicate)	Radiopacity confirmed to ensure visibility for colonic transit evaluation.
Marker Transit Characteristics	(Implied to be effective)	Studies showed markers <8mm ensure proper gastric emptying. Studies showed ring-formed, tube-formed, and cube-formed markers had identical transit.	N/A (Comparative evaluation for design choice)	The design choices (marker size and shape) are supported by studies indicating effective and consistent transit.
Ingestion and Imaging Protocol	Fixed dose, multiple days, several abdominal radiographs may be necessary.	10 markers/day for 6 days. On day 7, single abdominal radiograph. Segmental transit possible.	X	The protocol is similar in concept, with a specified count of markers and a final radiograph taken on day 7. The exact daily split (5 in morning/5 in evening) allows for measurement across the range of transit times.

2. Sample sized used for the test set and the data provenance

As this is a physical device and not an AI/ML algorithm, there are no "test sets" in the sense of image datasets used to evaluate an algorithm's performance. The performance evaluation relies on:

Bench testing: Simulated capsule digestion, dimensional analysis, mass analysis, radiopacity testing.
Biocompatibility testing: In vitro and in vivo studies on materials.
Clinical literature: Referenced to support design choices (e.g., marker size and shape influence on transit).
Comparison to predicate device: Demonstrating equivalence in function and safety.

No specific sample sizes for clinical performance studies are provided, as the substantial equivalence largely relies on the predicate's established performance and material/design testing. The document states "Clinical data was not required to establish the substantial equivalence of the subject and predicate devices." This indicates that extensive de novo clinical trials were not performed or submitted for this 510(k) clearance due to the device's similarity to an already cleared predicate.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

Not applicable. Ground truth for an AI device (e.g., image annotations by experts) is not relevant for this physical device. The "ground truth" for the device's function is the established physiological process of colonic transit and the ability to visualize markers to determine it.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

Not applicable. No expert review/adjudication of a test set is described.

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

Not applicable. This is not an AI-assisted diagnostic device.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

Not applicable. This is not an AI algorithm.

7. The type of ground truth used (expert concensus, pathology, outcomes data, etc)

Not applicable in the context of an AI device. For this device, the "ground truth" is the physical behavior of radiopaque markers in the human gastrointestinal tract, as understood and measured by established medical principles and imaging techniques. The performance is validated indirectly by:

Physical and chemical properties: Ensuring markers are radiopaque, stable, and release from capsules as intended.
Biocompatibility: Demonstrating safety of materials in physiological conditions.
Physiological principles: Relying on existing medical understanding of how different marker sizes/shapes traverse the GI tract and how the number/position of markers relates to colonic transit time.

8. The sample size for the training set

Not applicable. This is not an AI/ML algorithm that requires a training set.

9. How the ground truth for the training set was established

Not applicable.

Summary

{0}------------------------------------------------

Image /page/0/Picture/0 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). On the left is the seal of the Department of Health & Human Services. To the right of the seal is the FDA logo, which consists of the letters "FDA" in a blue square, followed by the words "U.S. FOOD & DRUG" in blue, and the word "ADMINISTRATION" in a smaller font size below.

August 8, 2019

Medifactia AB % Connie Qiu Regulatory Consultant III M Squared Associates, Inc 575 8th Ave Suite 1212 New York, NY 10018

Re: K181760

Trade/Device Name: Transit-Pellets Regulation Number: 21 CFR 876.1725 Regulation Name: Gastrointestinal Motility Monitoring System Regulatory Class: Class II Product Code: FFX Dated: December 27, 2018 Received: July 12, 2019

Dear Connie Qiu:

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

{1}------------------------------------------------

requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 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 (OS) 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,

for

Martha W. Betz, PhD Acting Assistant Division Director DHT3A: Division of Renal, Gastrointestinal, Obesity and Transplant Devices OHT3: Office of Gastrorenal, ObGyn, General Hospital and Urology Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

{2}------------------------------------------------

Indications for Use

510(k) Number (if known) K181760

Device Name Transit-Pellets

Indications for Use (Describe)

For evaluation of colonic transit in adult patients with chronic constipation and used to aid in differentiating slow and normal constipation.

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)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.

The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff PRAStaff@fda.hhs.gov

"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."

{3}------------------------------------------------

510(k) number: K181760

In accordance with 21 CFR 807.92, the following information constitutes the Medifactia AB summary for the Transit-Pellets.

Submission Date l.

July 11, 2019

II. Submitter Medifactia AB

Lumaparksvagen 7 Stockholm SE 120 30 Sweden Contact person: Diana Nyström Phone number: +46 (0) 31-787 70 77 E-mail: diana.nystrom@medifactia.com

Official Correspondent: Connie Qui Regulatory Consultant M Squared Associates, Inc. 575 8th Avenue, Rm 1212 New York, New York 10018 Ph: 347-954-0411 Fax: 702-562-9797 E-mail: CQui@Msquaredassociates.com

III. Device

Name of device: Transit-Pellets Common or usual name: Radiopaque markers Classification name: Gastrointestinal motility monitoring system Regulatory number: 21 CFR 876.1725 Regulation Class: II Product code: FFX Panel: Gastroenterology/Urology

IV. Predicate device

510(k)	Company	Device
K881609	Lafayette Pharmacal, Inc	Sitzmarks

{4}------------------------------------------------

V. Device Description

VI. Intended use

For evaluation of colonic transit in adult patients with chronic constipation and used to aid in differentiating slow and normal constipation.

Device name	Company Device	Predicate Device	SE
Applicant	Medifactia ABTransit-Pellets	Lafayette Pharmacal, IncSitzmarks
K#	--	K881609
Indication for useIntended use	For evaluation of colonictransit in patients withchronic constipation andused to aid in differentiatingslow and normalconstipation.	For evaluation of colonictransit in patients withchronic constipation andused to aid indifferentiating slow andnormal constipation.	X
Application	Measuring and usingcolonic transit time toevaluate patients withchronic (severe)constipation.	Measuring and usingcolonic transit time toevaluate patients withchronic (severe)constipation.	X
Target population	Adult patients with chronic(severe) constipation.	Adult patients with chronic(severe) constipation.	X
Anatomical site	Gastrointestinal tract/colon	Gastrointestinal tract/colon	X
Where used	Hospitals, clinics	Hospitals, clinics	X
Device name	Company Device	Predicate Device	SE
Applicant	Medifactia AB	Lafayette Pharmacal, Inc
	Transit-Pellets	Sitzmarks
Design	Ring-formed and tube-formed markers.	Three different shapes ofmarkers: O Rings, DoubleD and Tri-Chamber.	X
Dimensions	2 x 4.5mm, 6 x 2mm	1mm x 4.5mm	X
Materials	Markers: Barium sulphate,Elastosil® R 401/60Silicone rubberCapsules: HPMC,Hydroxypropyl-methylcellulose	Copied fromwww.sitzmarks.com:Markers: Rings-Polyvinylchloride, Bariumsulphate, DEHP, soya oil,calcium, zinc, phosphate,ultramarine tinting agent,mono & diglycerides, DOPplasticizerCapsules: HypromellosaCopied from 510(k);Markers: Radiopaquepolyvinyl chlorideGelatin capsules	X
Principle ofoperation	Patient swallows a fixeddose radiopaque marker fora number of days. On day7 a single abdominalradiograph or fluoroscopyis taken. Based on thenumber of retained markerson abdominal film and theirposition in colon a colonictransit time is calculatedand compared to referencevalue.	Patient swallows a fixeddose radiopaque markerfor a number of days.Several abdominalradiographs may benecessary. Based on thenumber of retainedmarkers on abdominalfilm(s) and their position incolon a colonic transit timeis calculated andcompared to referencevalue.	X
Performance	Colonic Transit Time(CTT/OATT) numericalvalues reported in days.ASTM F640-12 ROconfirmed.	Colonic Transit Time(CTT/OATT) numericalvalues reported in hours.	X
Biocompatibility	Yes, safe for intended useISO 10993-5ISO10993-10ISO 10993-11	No information
Packaging	Blister and folding box	Blister and folding box	X
Sterile	No	No	X
Shelf Life	2.5 years	unknown	X
Rx Only	Yes	Yes	X

VII. Comparison of the technology characteristics with the predicate devices

{5}------------------------------------------------

{6}------------------------------------------------

VIII. Performance testing

Transit-Pellets have a size <8mm and are made tube-formed and ring-formed. To test transit characteristics of various types of markers, five types of distinguishable markers in the specific gravity range 1.2-1.6 were examined. The size of the particles was chosen in the range 2-7 mm so that emptying from stomach was likely to occur also with a meal. In studies with markers of increasing sizes it was observed that markers with a size >8 mm will have a slower emptying rate from the stomach and thus the transit time from the stomach to the colon will be delayed and can lead to a falsely prolonged value of colonic transit time. Studies with markers <8 mm but of different shape showed that the transit through colon was identical with ring-formed, tube-formed and cube-formed markers. For these reasons, the Transit-Pellets were designed for their size and configurations and are safe and effective for their intended use when compared to the predicate device. Simulated capsule digestion testing in a simulated gastric fluid, dimensional analysis, and mass analysis, as well as the clinical literature provided in the 510k submission, confirms the device performs as intended for the proposed indication for use, i.e., is safe and effective for evaluation of colonic transit in patients with chronic constipation and used to aid in differentiating slow and normal constipation. The Transit-Pellets is substantially equivalent to Sitzmarks regarding material, technological characteristics, and indications for use.

Biocompatibility testing to ISO 10993-5 and -10 of the Transit-Pellets confirm the device is non-cytotoxic, non- irritant, and non-sensitizing. Testing to ISO 10993-11 confirmed that the Transit-Pellet extracts did not induce a significantly greater biologic reaction than the control following systemic injection and produced a non-pyrogenic response. Additionally, 14 Day Repeat IV and Intraperitoneal Toxicity in Rats did not demonstrate systemic signs of toxicity over 14 days.

Radiopacity Testing in accordance with ASTM F640-12 confirms visibility of the Transit-Pellets for the duration and environment of their intended use during colonic transit.

IX. Clinical Data

Clinical data was not required to establish the substantial equivalence of the subject and predicate devices.

X. Conclusion

The two devices share the indication for use of measuring and using colonic transit time to evaluate patients with chronic constipations of our device cover the application of the predicate device and thus the difference will not affect safety and efficiency.

The information provided in this510(k)support that the Transit-Pellets is substantially equivalent in function, composition, and intended use to the predicate devices. The proposed device raises no new issues of safety and effectiveness.

Regulation Number and Section

§ 876.1725 Gastrointestinal motility monitoring system.

(a)
Identification. A gastrointestinal motility monitoring system is a device used to measure peristalic activity or pressure in the stomach or esophagus by means of a probe with transducers that is introduced through the mouth into the gastrointestinal tract. The device may include signal conditioning, amplifying, and recording equipment. This generic type of device includes the esophageal motility monitor and tube, the gastrointestinal motility (electrical) system, and certain accessories, such as a pressure transducer, amplifier, and external recorder.(b)
Classification. Class II (performance standards).