FAQ

Overview

What is SERI^® Surgical Scaffold?
SERI^® Surgical Scaffold is the first and only Silk-derived Biological Scaffold—not derived from human cadaver or animal tissue. Specifically, SERI^® Surgical Scaffold is a knitted, multifilament, bioengineered, long-term bioresorbable scaffold.² It is derived from silk that has been purified to yield ultra pure fibroin.² The product is a mechanically strong and biocompatible bioprotein.²

What makes SERI^® Surgical Scaffold a unique approach to tissue generation?
Through bioreplacement, SERI^® Surgical Scaffold facilitates the generation of native, well-vascularized tissue that is ≈ twice the starting thickness of the scaffold alone at 24 months.^1,* This newly ingrown tissue was shown to exhibit nearly twice the average strength of ovine fascia at 24 months—and supported the majority of load-bearing responsibility.^1,*

What is the indicated use for SERI^® Surgical Scaffold?
SERI^® Surgical Scaffold is indicated for use as a transitory scaffold for soft tissue support and repair to reinforce deficiencies where weakness or voids exist that require the addition of material to obtain the desired surgical outcome. This includes reinforcement of soft tissue in plastic and reconstructive surgery, and general soft tissue reconstruction.²

Are there any contraindications for using SERI^® Surgical Scaffold?
Yes, SERI^® Surgical Scaffold is contraindicated in 2 situations²:

1. Patients with a known allergy to silk
2. Direct contact with bowel or viscera where formation of adhesions may occur

What are key features of SERI^® Surgical Scaffold?

• SERI^® Surgical Scaffold is an ultra pure, sterile, silk-derived bioprotein—not derived from human cadaver or animal tissue²
• SERI^® Surgical Scaffold facilitates neovascularization (as early as 2 days)^† and native tissue generation over time^1,*
• Through bioreplacement, SERI^® Surgical Scaffold facilitates the generation of native, well-vascularized tissue that is ≈ twice the starting thickness of the scaffold alone at 24 months^1,*
• Native tissue provides lasting support and strength through 24 months^1,*
• At 24 months, native tissue demonstrated nearly twice the average strength of ovine fascia^1,*
• SERI^® Surgical Scaffold exhibits favorable integration and predictable bioresorption over time^1,*^,†,‡
• SERI^® Surgical Scaffold demonstrated substantial bioreplacement through 24 months^1,*

What studies were conducted to demonstrate the performance of SERI^® Surgical Scaffold?
SERI^® Surgical Scaffold is a 510(k)-cleared product. Multiple bench, animal, and human studies have been conducted, supporting its suitability for use.

What human data are available for SERI^® Surgical Scaffold?
Sofregen continues to conduct ongoing clinical studies to further evaluate the performance of SERI^® Surgical Scaffold for soft tissue support and repair. For more information on these clinical studies, please contact Sofregen Medical Affairs at (617) 651-8871 or visit ClinicalTrials.gov.

What animal data are available for SERI^® Surgical Scaffold?
Multiple animal model studies have been conducted to evaluate the performance of SERI^® Surgical Scaffold. One was an ovine subcutaneous thoracic wall implant study designed to measure the strength and thickness of SERI^® Surgical Scaffold and newly generated native tissue at up to 24 months after implantation of SERI^®.¹ In another study using SERI^® Surgical Scaffold in a rat model of abdominal wall defect, SERI^® Surgical Scaffold plus tissue samples were taken and analyzed at various time points up to 4 weeks after implantation, showing neovascularization (as early as 2 days).¹ A rat abdominal wall model study was also conducted to evaluate cell and tissue response to intramuscular implantation of SERI^® Surgical Scaffold fibers and Sofsilk^® nonresorbable silk sutures 28 days after implantation using histology.¹

Neovascularization

What is the difference between neovascularization and revascularization?
“Neovascularization” refers to the ingrowth of new blood vessels.⁶ As shown in a rat model of abdominal wall defect, SERI^® Surgical Scaffold facilitates neovascularization (as early as 2 days).^1,* As SERI^® Surgical Scaffold integrates with native tissue at the site of implantation, it is gradually bioreplaced with well-vascularized tissue.^1,2,†,‡

“Revascularization” is defined as the reestablishment of blood supply to the tissue.⁶ This effect has been demonstrated in ADMs,⁷ as opposed to the neovascularization associated with SERI^® Surgical Scaffold.^1,*

How quickly does neovascularization begin to take place with SERI^® Surgical Scaffold?
SERI^® Surgical Scaffold facilitates neovascularization (as early as 2 days), as demonstrated in a rat model study.^1,*

What does it mean when the patient’s tissue is “well vascularized”?
Well-vascularized tissue has sufficient blood supply to maintain cellular function.^6,8

Why is well-vascularized tissue important?
Well-vascularized tissue ensures that cells have an adequate supply of oxygen to carry out cellular activities.⁸

Native Tissue Generation

What resulting tissue thickness can be expected with SERI^® Surgical Scaffold?
As seen in a full-scale animal model study, SERI^® Surgical Scaffold and newly generated tissue demonstrated thickness at 3 months.^1,* In the same study, native tissue contributed approximately twice the starting thickness of the scaffold alone at 24 months.^1,* At this point, most of SERI^® Surgical Scaffold has been bioreplaced with native, well-vascularized tissue—meaning the resulting thickness comes almost entirely from the newly ingrown tissue.^1,*

How does tissue generated with SERI^® Surgical Scaffold differ from scar tissue?
SERI^® Surgical Scaffold demonstrates neovascularization and tissue ingrowth.^1,*^,† A histology image taken from a rat model study at 4 weeks post implant shows noticeable tissue ingrowth, fiber bundles, and blood vessels around the threads of SERI^® Surgical Scaffold—which exhibits neovascularization.^1,†

Unlike the native tissue generated in and around SERI^® Surgical Scaffold, scar tissue may exhibit dense, compacted fibers and minimal to no vascularization.^1,† This is shown in a histology image of scar tissue taken from a separate rat model study at 7 weeks post implant.^1,†

Support and Strength

How strong was native tissue ingrowth with SERI^® Surgical Scaffold?
As SERI^® Surgical Scaffold is bioresorbed, the support and strength slowly shift from SERI^® Surgical Scaffold to the newly ingrown tissue.^1,2,* According to a full-scale animal (ovine) model study, native tissue provides lasting support and strength through 24 months.^1,* These data demonstrate that newly generated tissue provided the majority of load-bearing strength by 6 months.^1,* In addition, native tissue demonstrated nearly twice the average strength of ovine fascia at 24 months—and supported the majority of load-bearing responsibility.^1,*

*Methodology: In an ovine subcutaneous thoracic wall implant study designed to measure the strength and thickness of SERI^® Surgical Scaffold and newly generated native tissue at up to 24 months after implantation of SERI^®.¹
Note: Similar studies in humans have not been performed.

Bioreplacement

What does it mean that SERI^® Surgical Scaffold is bioresorbable?
SERI^® Surgical Scaffold is broken down naturally by the body through cellular digestion as native, vascularized tissue is generated in its place.^1,*^,†

Does SERI^® Surgical Scaffold completely bioresorb? If so, when?
SERI^® Surgical Scaffold is designed to slowly bioresorb in parallel to neovascularization and native tissue ingrowth, which results in eventual replacement of SERI^® Surgical Scaffold with native tissue.² It all begins with integration—as early as 2 days after implantation.^1,†,‡ The tissue response to SERI^® Surgical Scaffold demonstrates integration and neovascularization as the scaffold is bioreplaced over time with collagen.^1,*^,†,‡ In a full-scale animal model study, substantial bioreplacement of SERI^® Surgical Scaffold was evident by 24 months.^1,*

Biocompatibility

Is there an immune or inflammatory response to SERI^® Surgical Scaffold?
Because SERI^® Surgical Scaffold is a silk-derived bioprotein that has undergone a purification process designed to remove sericin and other impurities,² no immune response has been observed in preclinical studies.^1,*^,†

Following implantation, the patient’s tissue initiates a normal wound-healing response.^1,† As part of the process, SERI^® Surgical Scaffold elicits a mild-moderate inflammatory response that is confined to the silk-derived scaffold.^1,†,‡ Neovascularization takes place as SERI^® Surgical Scaffold is bioreplaced over time with newly ingrown tissue composed of organized collagen and blood vessels.^1,2,*^,†

How does the silk in SERI^® Surgical Scaffold differ from ordinary silk?
Ordinary silk sutures contain sericin, which is associated with an exaggerated inflammatory response.⁵ Only SERI^® Surgical Scaffold undergoes the Sofregen proprietary purified bioengineering process, which is designed to remove sericin and other impurities from the raw silk fibers—creating a terminally sterilized, ultra pure product.^2,4,9

How does SERI^® Surgical Scaffold interact differently with the patient’s tissue compared to commercial silk sutures?
The components in silk sutures, such as sericin, can cause excessive inflammation.⁵ In addition, the silk fibers are braided and may be dyed and coated with wax or silicone.⁵ Silk sutures typically can become encapsulated and do not integrate into the native tissue, as shown at 28 days post implantation in a rat abdominal wall model.^1,‡

Ultra pure SERI^® Surgical Scaffold undergoes the Sofrefen proprietary purified bioengineering process designed to remove sericin and other impurities from the raw silk fibers.^2,4 Because of this purification and other steps, SERI^® Surgical Scaffold demonstrates favorable integration and predictable bioresorption.^1,*^,†,‡ In addition, tissue response to SERI^® Surgical Scaffold exhibits minimal inflammation that is confined to the silk-derived scaffold. This helps promote favorable integration and neovascularization as the scaffold is bioreplaced over time with collagen.^1,*^,‡

Adverse Reactions/Limitations for Use

What adverse reactions may occur with the use of SERI^® Surgical Scaffold?
Adverse reactions are those typically associated with surgically implantable materials, including infection, inflammation, adhesion formation, fistula formation, and extrusion.²

Are there any limitations to using SERI^® Surgical Scaffold in pregnant women?
Caution should be used when implanting SERI^® Surgical Scaffold in pregnant women. The use of a product that can impede tissue expansion may be hazardous during pregnancy.²

What contraindications are associated with the use of SERI^® Surgical Scaffold?
Do not use SERI^® Surgical Scaffold in patients with a known allergy to silk or for direct contact with bowel or viscera where formation of adhesions may occur.²

Product Characteristics

What characteristics make SERI^® Surgical Scaffold consistent and predictable?
Sofregen starts with a consistent raw source material and continues to refine and eliminate variability in product characteristics through our proprietary purified bioengineering process.^1,2 The end result is an ultra pure biomaterial with predictable strength, consistency, and sterility out of the package.^1,2

How was SERI^® Surgical Scaffold designed for ease of use?
Ease of use is important in a surgical setting, which is why SERI^® Surgical Scaffold was created with the following attributes:

• Proprietary knit design is tear resistant and easy to cut in any direction without unraveling^1,2
• Macropores for suture retention and enhanced visibility while suturing²
• Easily drapable over the defect site during implantation¹
• No rehydration necessary—SERI^® Surgical Scaffold is ready for immediate use out of the package.² However, a brief dip (minimum 2 to 3 seconds) in standard sterile rinse solution is recommended prior to implantation²
• Does not require refrigeration; SERI^® Surgical Scaffold should be stored at room temperature in a dry area²
• The shelf life of each SERI^® Surgical Scaffold package is 3 years from the date of sterilization¹; there is an expiration date printed on each package

Can SERI^® Surgical Scaffold be cut to a desired size/shape?
Yes, SERI^® Surgical Scaffold may be cut but this should be followed by proper rinsing and aspiration.² The product’s proprietary knit design makes it easy to cut in any direction without unraveling.^1,2

How is SERI^® Surgical Scaffold manufactured?
SERI^® Surgical Scaffold undergoes the Sofregen proprietary purified bioengineering process.² This is designed to remove sericin and other impurities from natural silk to create an ultra pure, sterile product.^2,4 The manufactured material is knitted together to exact and consistent specifications.^1,2

Why does SERI^® Surgical Scaffold feel different out of the package compared to when it is wet?
When SERI^® Surgical Scaffold is rinsed or soaked, the 3-dimensional scaffold structure becomes hydrated with fluid molecules surrounding the fibers. However, this does not affect the performance of SERI^® Surgical Scaffold.¹

What is the effect of folding SERI^® Surgical Scaffold on top of itself? Will that make it stronger, and will the resulting tissue be thicker?
Each unfolded single layer of SERI^® Surgical Scaffold has been custom engineered to an exact size, shape, strength, elasticity, flexibility, thickness, and knit design. Use of multiple layers of SERI^® Surgical Scaffold has not been tested.²

Product Preparation

How is SERI^® Surgical Scaffold prepared for use in the patient?
Although SERI^® Surgical Scaffold does not require rehydration for mechanical or physical performance, a brief dip (minimum 2 to 3 seconds) in standard sterile rinse solution is recommended prior to implantation.² Ideally, it should be trimmed prior to implantation—followed by extensive rinsing in standard sterile rinse solution.²

Why does Sofregen recommend a brief dip in standard sterile rinse solution prior to implantation of SERI^® Surgical Scaffold?
This recommendation is based on standard surgical practice.

Can SERI^® Surgical Scaffold be re-sterilized prior to use?
No. SERI^® Surgical Scaffold is already provided as a sterile, single-use-only product.² Autoclaving, the use of ethylene oxide (EO) gas, and other sterilization processes may compromise the product’s performance and patient safety.

Does SERI^® Surgical Scaffold require refrigeration or rehydration prior to use?
SERI^® Surgical Scaffold does not require refrigeration; it should be stored at room temperature in a dry area.²

Although SERI^® Surgical Scaffold does not require rehydration for mechanical or physical performance, a brief dip (minimum 2 to 3 seconds) in standard sterile rinse solution is recommended prior to implantation.²

How should SERI^® Surgical Scaffold be stored and handled?
SERI^® Surgical Scaffold should be stored in its original sealed package away from direct sources of heat at room temperature.² SERI^® Surgical Scaffold should be handled using aseptic techniques and sterile talc-free gloves.²

Are both sides of SERI^® Surgical Scaffold the same?
Both sides of SERI^® Surgical Scaffold are identical, which means either side can be placed against a soft tissue defect.¹

Miscellaneous

Can SERI^® Surgical Scaffold be reimbursed?
Sofregen is committed to surgeons and facilities using SERI^® Surgical Scaffold to help their patients. That’s why we are dedicated to answering all of your reimbursement, coding, and billing questions about this product. For assistance in these areas, please contact SERI^® Surgical Scaffold Reimbursement Support at (518) 708-3455.

How long does each package of SERI^® Surgical Scaffold last?
The shelf life of each SERI^® Surgical Scaffold package is 3 years from the date of sterilization.¹ There is an expiration date printed on each package.

Does SERI^® Surgical Scaffold impact drainage strategy?
SERI^® Surgical Scaffold has a macroporous design² that may allow for fluid ingress and egress. However, drainage strategy with SERI^® Surgical Scaffold has not been studied. It is recommended that you follow your current drainage strategy.

Are there plans for other SKUs with different sizes, shapes, elasticity, thicknesses, knit patterns, etc?
Yes. The textile engineering of SERI^® Surgical Scaffold has been designed to allow for future development of various product characteristics, based on surgeon needs.

Is SERI^® Surgical Scaffold palpable through the skin?
In a full-scale animal model study, SERI^® Surgical Scaffold was not typically palpable through the skin after being implanted for 3 months.^1,* As SERI^® Surgical Scaffold integrates with native tissue at the site of implantation, it is gradually bioreplaced with newly ingrown, well-vascularized tissue.^1,*^,†

What is the compatibility of SERI^® Surgical Scaffold with imaging?
In a full-scale animal model study, SERI^® Surgical Scaffold did not interfere with either computerized tomography or magnetic resonance imaging.^1,*

What is the difference between the courses and wales in a knitted structure like SERI^® Surgical Scaffold?
A course is a vertical row of needle loops, and a wale is a horizontal row of intermeshed needle loops. When looking at the scaffold closely, you will see a thicker row (the wale) and a looser column (the course).¹

Product Landscape

Are there other silk-derived soft tissue support and repair products like SERI^® Surgical Scaffold on the market?
No, SERI^® Surgical Scaffold is the first and only Silk-derived Biological Scaffold.

What are the benefits of using SERI^® Surgical Scaffold?
According to a full-scale animal model study, native tissue provides lasting support and strength through gradual bioreplacement.^1,* As SERI^® Surgical Scaffold integrates with native tissue at the site of implantation, it is gradually bioreplaced with well-vascularized tissue.^1,*^,†

In addition, SERI^® Surgical Scaffold eliminates the variability in product characteristics associated with donated human or animal tissue.¹ The proprietary purified bioengineering process delivers consistent, predictable properties, ensuring a sterile, homogeneous product.^1,2

What makes SERI^® Surgical Scaffold different from allografts?
Through bioreplacement, SERI^® Surgical Scaffold facilitates the generation of native, well-vascularized tissue that is ≈ twice the starting thickness of the scaffold alone at 24 months, as shown in a full-scale animal model study.^1,* In addition, only SERI^® Surgical Scaffold—a product not derived from human cadaver or animal tissue—undergoes a proprietary purified bioengineering process to deliver consistent, predictable properties.^1,2

There may be some variability in product characteristics associated with donated human tissue in allografts.

What makes SERI^® Surgical Scaffold different from xenografts?
As shown in animal model studies, SERI^® Surgical Scaffold facilitates neovascularization (as early as 2 days) and generates strong, native tissue by 24 months.^1,*^,‡ Not derived from human cadaver or animal tissue, SERI^® Surgical Scaffold delivers continuous soft tissue support through gradual bioreplacement.^1,2,* In addition, newly generated tissue was shown to provide nearly twice the average strength of ovine fascia at 24 months.^1,* Furthermore, the proprietary purified bioengineering process delivers consistent, predictable properties, ensuring a sterile, homogeneous product—from package to package.^1,2

There may be some variability in product characteristics associated with donated animal tissue in xenografts.

Are there any head-to-head clinical studies comparing SERI^® Surgical Scaffold vs AlloDerm^®?
Currently, there are no head-to-head clinical studies evaluating the performance of SERI^® Surgical Scaffold vs AlloDerm^®.

Are there any head-to-head clinical studies comparing SERI^® Surgical Scaffold vs Strattice^®?
Currently, there are no head-to-head clinical studies evaluating the performance of SERI^® Surgical Scaffold vs Strattice^®.