`BI I-125 BRACHYTHERAPHY SEED, MODEL 125SL & 125SH
Applicant
Urocor, Inc.
Product Code
KXK · Radiology
Decision Date
Apr 16, 1999
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 892.5730
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
MBI I-125 Brachytherapy Seeds with apparent activities between 3.7 MBq (0.1 mCi) to 37 MBq (1.0 mCi) are indicated for permanent interstitial treatment of tumors which are unresectable or residual after excision of the primary lesion, localized, slow growing, and exhibit low to moderate radiosensitivity. Intra abdominal, intrathoracic and superficial tumors may be treated with seeds containing apparent activities within this range. Tumors commonly treated are prostate (early stage), pancreas, head, neck, and lung. MBI I-125 Brachytherapy Seeds containing apparent activities greater than 37 MBq (1.0 mCi) are indicated for temporary interstitial treatment of tumors which are unresectable or residual after excision of the primary lesion, localized, and exhibit moderate radiosensitivity. Temporary implants are indicated in breast, brain and eye tumors. MBI I-125 Brachytherapy Seeds are indicated for treatment of residual tumors and recurrent tumors following external radiation therapy, hyperthermia, or chemotherapy or concurrent use with these treatment modalities.
Device Story
MBI I-125 Brachytherapy Seed is a radioactive implant for interstitial tumor treatment. Device consists of titanium cylindrical casing (4.55mm length, 0.865mm diameter) containing iodine-125 adsorbed onto three to five silver spheres; silver spheres provide X-ray contrast for visualization. Seeds are implanted into tumors by clinicians; permanent implants used for slow-growing, low-to-moderate radiosensitivity tumors; temporary implants used for moderate radiosensitivity tumors. Radiation emission provides localized therapeutic dose to tumor tissue. Device serves as alternative to existing brachytherapy seeds for managing unresectable or residual lesions, including recurrent cases post-chemotherapy or external radiation.
Clinical Evidence
Bench testing only. Photon emission spectra measured via intrinsic Ge detector showed five energy peaks (22.1, 25.5, 27.4, 31.4, 35.5 keV). Radiation fluence distribution analyzed via polar coordinate plotting at 1-meter distance. Results demonstrate consistency with predicate Model 6711 and published dosimetry literature (Ling et al., 1983).
Technological Characteristics
Titanium casing (0.06mm wall thickness); laser-welded ends. Internal structure: 3-5 silver spheres with adsorbed I-125. Dimensions: 4.55mm length, 0.865mm diameter. Energy source: I-125 radionuclide. Radiographic visualization via silver spheres.
Indications for Use
Indicated for patients with unresectable or residual localized tumors (prostate, pancreas, head, neck, lung, breast, brain, eye) exhibiting low to moderate radiosensitivity. Used for permanent interstitial treatment (3.7-37 MBq) or temporary interstitial treatment (>37 MBq). Indicated for residual/recurrent tumors post-external radiation, hyperthermia, or chemotherapy.
Regulatory Classification
Identification
A radionuclide brachytherapy source is a device that consists of a radionuclide which may be enclosed in a sealed container made of gold, titanium, stainless steel, or platinum and intended for medical purposes to be placed onto a body surface or into a body cavity or tissue as a source of nuclear radiation for therapy.
Special Controls
*Classification.* Class II (special controls). A prostate seeding kit intended for use with a radionuclide brachytherapy source only is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.
Predicate Devices
Model 6711 by Amersham/Medi-Physics, Inc. (K914281)
Submission Summary (Full Text)
{0}------------------------------------------------
K984446
## Premarket Notification 510(k) Summary
Mills Biopharmaceuticals, Inc. 120 N.E. 26th Street Oklahoma City, Oklahoma 73105 Phone 405-525-3141 Fax 405-525-3143 Contact Person: Stanley L. Mills, Ph.D. Date of Summary Preparation: 10 December 1998
| Device Classification | |
|-----------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Name: | SOURCE, BRACHYTHERAPY, RADIONUCLIDE |
| Trade Name: | MBI I-125 Brachytherapy Seed |
| Common Name: | I-125 Brachytherapy Seed |
| Equivalence: | Model 6711 by Amersham/Medi-Physics, Inc.(K914281) |
| Description: | Each MBI I-125 Brachytherapy Seed external dimensions of 4.55 mm ± 0.35 mm in length and 0.865 mm ± 0.095 mm in diameter. The cylindrical metal casing is titanium having a wall thickness of 0.06 mm ± 0.02 mm laser welded at both ends. Both models: 125SL and 125SH have three to five silver spheres which are used to absorbed iodine-125 and provide X-ray contrast. |
| Intended use: | MBI I-125 Brachytherapy Seeds with apparent activities between 3.7 MBq (0.1 mCi) to 37 MBq (1.0 mCi) are indicated for permanent interstitial treatment of tumors which are unresectable or residual after excision of the primary lesion, localized, slow growing, and exhibit low to moderate radiosensitivity. Intra abdominal, intrathoracic and superficial tumors may be treated with seeds containing apparent activities within this range. Tumors commonly treated are prostate (early stage), pancreas, head, neck, and lung. MBI I-125 Brachytherapy Seeds containing apparent activities greater than 37 MBq (1.0 mCi) are indicated for temporary interstitial treatment of tumors which are unresectable or residual after excision of the primary lesion, localized, and exhibit moderate radiosensitivity. Temporary implants are indicated in breast, brain and eye tumors. MBI I-125 Brachytherapy Seeds are indicated for treatment of residual tumors and recurrent tumors following external radiation therapy, hyperthermia, or chemotherapy or concurrent use with these treatment modalities. |
| Technological<br>Characteristics: | Model 6711, Model 125SL, and 125SH all encapsulate with titanium and seal by welding the ends closed. Model 6711, I-125 Seeds differ from our design in the composition of the interior absorbing material. Model 6711, I-125 Seeds the I-125 is adsorbs onto a single silver rod which also provides for radiographic visualization. In the Model 125SL and 125SH the I-125 is adsorbed onto silver spheres which also provide radiographic visualization. |
{1}------------------------------------------------
NonClinical Data:
Photon emission spectra was determined using an intrinsic Ge detector. The spectrum was obtained transverse to the seed axis and consisted of three photon peaks of energy 27.4. 31.4. and 35.5 keV. In addition, two additional peaks at 22.1 and 25.5 keV were identified as fluorescent xrays from the silver spheres.
Total radiation fluence distribution data as determined by an intrinsic Ge detector analyzed with a multichannel analyzer. The I-125 seeds were mounted on a thin plastic rod capable of being precisely rotated about 360° in 5° increments. The mounting rod was designed to be adjusted to place the seed in the center of the detector and at a distance of one meter. Five I-125 seeds were analyzed along both the short and long axis. The data was averaged and plotted in the polar coordinate system where the radial distance represents the relative magnitude of photon fluence in various directions with respect to the seed axis.
Conclusion:
The photon emisson spectra and total radiation fluence distribution data is consistant between Amersham/Medi-Physics, Inc. Model 6711 and Mills Biopharmaceuticals, Inc. Model 125SL. The emission spectra consisted of five energy peaks at 22.1, 25.5, 27.4, 31.4, 35.5 keV. Total radiation fluence distribution is similar between the two different models when compared to published data for the Model 6711 (Ling, C.C., Yorke, E.D., Spiro, I.J., Kubiatowicz, D., Bennett, D .: Physical dosimetry of 1251 seeds of a new design for interstitial implant. Int. J. Radiation Oncology Biol. Phys., 9:1747-52, 1983).
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Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized eagle with three stripes forming its body and wing. The eagle is enclosed in a circle with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
APR 16 1999
Stanley L. Mills. Ph.D. Mills Biopharmaceuticals Incorporated 120 N.E. 26th Street Oklahoma City, OK 73105
Re:
K984446 MBI I-125 Brachytherapy Seed Models 125SL and 125SH Dated: March 26, 1998 Received: March 29, 1998 Regulatory class: II 21 CFR 892.5730/Procode: 90 KXK
Dear Dr. Mills:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we 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). You may, therefore, market the device, subject to the general controls provisions of the Act. 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.
If your device is classified (see above) into either class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in requlatory action. In addition. FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4613. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours,
CAPT Daniel G. Schultz, M.D. Acting Director, Division of Reproductive, Abdominal, Ear, Nose and Throat, and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
{3}------------------------------------------------
510(k) Number (if known):
K984446
Device Name: MBI I-125 Brachytherapy Seed
## INDICATIONS FOR USE:
MBI I-125 Brachytherapy Seeds with apparent activities between 3.7 MBq (0.1 mCi) to 37 MBq (1.0 mCi) are indicated for permanent interstitial treatment of tumors which are unresectable or residual after excision of the primary lesion, localized, slow growing, and exhibit low to moderate radiosensitivity. Intra abdominal, intrathoracic and superficial tumors may be treated with seeds containing apparent activities within this range. Tumors commonly treated are prostate (early stage), pancreas, head, neck, and lung.
MBI I-125 Brachytherapy Seeds containing apparent activities greater than 37 MBq (1.0 mCi) are indicated for temporary interstitial treatment of tumors which are unresectable or residual after excision of the primary lesion, localized, and exhibit moderate radiosensitivity. Temporary implants are indicated in breast, brain and eye tumors.
MBI I-125 Brachytherapy Seeds are indicated for treatment of residual tumors and recurrent tumors following external radiation therapy, hyperthermia, or chemotherapy or concurrent with these treatment modalities.
## (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
| Prescription Use | <div style="display:inline-block;"> <span style="text-decoration:overline;"></span> <span style="position:relative; top:-0.5em;">(Per 21 CFR 801.109)</span> </div> |
|----------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Over-The-Counter Use | <span style="text-decoration:overline;"></span> |
(Division Sign-Off)
Division of Reproductive, Abdominal, ENT,
and Radiological Devices
| 510(k) Number | <span style="text-decoration:overline;">K984446</span> |
|---------------|--------------------------------------------------------|
|---------------|--------------------------------------------------------|
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