FDA Approvals: Visian ICL and TricOs T

Yael Waknine

January 10, 2006

Jan. 10, 2006 — The US Food and Drug Administration (FDA) approved in 2005 a phakic intraocular collamer lens for the correction of myopia in adults, and a resorbable bone void filler for the repair of defects caused by trauma or surgery.


Phakic Intraocular Collamer Lens (Visian ICL) for Correction of Myopia in Adults

On December 22, the FDA approved a phakic intraocular collamer lens (Visian ICL, made by STAAR Surgical Company) for the correction of myopia ranging from –3 to –15 diopters (D) with astigmatism of 2.5 D or less at the spectacle plane, and for the reduction of myopia ranging from more than –15 to –20 D anterior, with astigmatism of 2.5 D or less at the spectacle plane.

The lens is intended for use in adults aged 21 to 45 years with an anterior chamber depth of 3 mm or greater, and a stable refractive history within 0.5 D for 1 year prior to implantation.

The lens is composed of a proprietary hydrophilic copolymer of collagen and hydroxyl-ethylmethacrylate that also contains a covalently bound UV chromophore (collamer), and can be folded for injection through a 3-mm incision.

According to a company news release, the collagen component repels the protein molecules that are attracted to silicone lenses and cause fibrosis, while attracting a monolayer of fibronectin that isolates the lens from the immune system to virtually eliminate the risk for inflammation.

In addition, the copolymer's molecular size (100 nm) is shorter than the wavelength of visible light, resulting in an optimal refractive index for maximum light transmission and minimal glare/halo.

The approval was based on data from a clinical study (n = 294) showing that 95% of patients had 20/40 vision or better and 59% had 20/20 vision or better at 3 years postimplantation.

The ICL was previously approved for use in Korea, Canada, and the European Union.


Resorbable Bone Void Filler (TricOs T) for Repair of Bone Defects

On November 28, 2005, the FDA approved a resorbable bone void filler (TricOs T, made by Baxter Healthcare Corporation) for use in voids or gaps that are not intrinsic to the stability of the bony structure, such as those caused by trauma or surgery. Because it does not have initial mechanical properties, rigid fixation techniques may be needed.

The bone substitute consists of a calcium phosphate scaffold (hydroxyapatite-coated beta tricalcium phosphate granules) combined with a 3-dimensional heterologous fibrin matrix that renders the product moldable and allows it to hold its shape. After placement in the gap, the biocompatible product is resorbed and replaced with bone during the healing process.

The approval was based on data from safety and efficacy studies showing the bone void filler to be substantially equivalent to commercially available predicate devices, including Allomatrix Putty (made by Wright Medical Technology, Inc), TCP Putty (made by Stryker Biotech), MBCP (made by Biomatlante), Collagraft Strip-Bone-Graft Matrix (made by NewColl, Inc), and JAX-tcp (made by Smith & Nephew, Inc).

According to a company news release, the product will be launched on the US market in the second half of 2006.

Reviewed by Gary D. Vogin, MD

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