Confidential

needs associated with surgical sealing and adhesion prevention Company Overview Platform technology of “in situ polymerized” biomaterials and delivery devices Targeting large potential markets in biosurgery, specifically: Adhesion Barriers and Sealants First to market products Products commercially available Initial targets in Neuro/Spine and broad applicability beyond initial targets Confluent’s vision is to be the leading developer of products for unmet needs associated with surgical sealing and adhesion prevention

Confluent Hydrogel Technology Proprietary "Reversible" Hydrogel Technology

Confluent’s Differentiation Technology Synthetic origin, very biocompatible Strong tissue adherence Products stored at room temperature Quick polymerization Ideal for minimally invasive surgery applications Strong IP and barrier to entry Business Model No separate reimbursement typically needed for products Leverages outsourcing High margins Minimal capital investment Easily scaled

The Need for Surgical Sealing Neuro and Spine Surgery CSF leaks can lead to neural compression, postural headaches, infection, meningitis, and death Vascular, Cardiac, and Orthopedic Surgery Bleeding can prolong surgery, transfusions create risk of disease transmission Thoracic and General Surgery Prolonged hospital stays, risk of infection, and morbidity

The Need for Adhesion Prevention Gynecological Infertility and pelvic pain due to adhesions General Surgery Bowel obstruction, pain, complicated re-operations Spine Surgery Failed back syndrome, re-do surgery may result in dural tears Cardiac Surgery Complicated re-do surgery, danger of myocardial incision

Confluent Hydrogel Products DuraSealTM – Achieve watertight dural closure, prevent CSF leakage following cranial surgery Commercially available in U.S. and select international markets In pivotal clinical trial in U.S. for spinal sealing SprayGel® – Reduce the formation of post-surgical abdominopelvic adhesions Commercially available in select international markets, under clinical trials in U.S.

DuraSeal Surgical Sealant Target Market Cardiac $$ Large need for surgical sealants (neuro, spine, general, vascular, thoracic, and plastic) $$ initial target opportunity for Confluent DuraSeal will be first dural sealant in U.S. Additional markets can be accessed with technology platform Neuro $$ Vascular $$ Thoracic $$

DuraSeal – Mechanism of Action Intended Use: Duraseal is intended for use as an adjunct to sutured cranial dural repair to provide watertight closure. When applied, DuraSeal: Rapidly diffuses into tissue crevices and crosslinks Interlocks within tissue crevices resulting in excellent tissue adherence Blue colorant allows for visualization of gel coverage and thickness

DuraSeal – Mechanism of Action DuraSeal can withstand elevated CSF pressures due to: Strong tissue adherence High cohesive strength Biomimetic elasticity

DuraSeal – Mechanism of Action Post operative attributes: Separates dura from the bone flap preserving the tissue plane May facilitate subsequent re-operation

DuraSeal – Mechanism of Action Biocompatible absorption: Water soluble linkages hydrolyze over # weeks Water soluble PEG molecules are liberated and cleared via the kidneys

DuraSeal – Mechanism of Action DuraSeal Benefits for cranial surgeries: Creates an immediate watertight seal Blue colorant allows for visualization of gel coverage and thickness Reduces postoperative CSF leaks Safely absorbs after the body has naturally healed Easily prepared in # minutes

DuraSeal - Clinical Data* Pilot Study (Reference) Single arm study in patients for intradural cranial and spinal procedures 100% intraoperative sealing of the dura was observed ##% post-operative leak rate and ##% pseudomeningocele rate observed Pivotal Study (Reference) Single arm study in ## patients for intradural cranial procedures ##% intraoperative sealing of the dura was observed #% post-operative leak rate and #% pseudomeningocele rate observed *Expected rate of postoperative CSF leakage is about ##% and cost of a single CSF leak is estimated to be around $$$

DuraSeal - MicroMyst Applicator Cleared in U.S. CE Mark in EU For use in Spine and transsphenoidal procedures

DuraSeal Spine Sealing “Zero Swelling” Version of DuraSeal Durotomy Sealant application

SprayGel Adhesion Barrier Status OUS: CE Mark US: Clinical trials Large clinical need for post- surgical adhesion prevention (gynecological, abdominal and pelvic surgery) Initial target opportunity for Confluent SprayGel is the world’s first sprayable local adhesion barrier Pilot trial in Gynecology has shown 70% reduction in incidence and extent of adhesions Trial in General Surgery underway and pivotal trial in Laparoscopy planned Worldwide Adhesion Barrier Market Abdominal $ Gynecologic SprayGel Air-assisted Applicator

Product Pipeline

Product Roadmap and Strategy Overall Market Opportunity Size Time

DuraSeal - Drug Delivery % Analgesic Released % Antibiotic Released Days at 37°C Days at 37°C Controlled release demonstrated with: Antibiotics Analgesics Antiproliferatives Anti-inflammatories

Intellectual Property Position 13 issued patents Additional 12 patents pending Broad coverage of fundamentals Creates substantial barrier-to-entry Composition of matter, method of use, delivery device technology

Competitive Environment DuraSeal – None for craniotomy. Other indications include: Cryolife and Baxter Strength Preparation Time CoSeal DuraSeal HemaSeel Burst (amount / amount) HemaSeel CoSeal DuraSeal Time

Financial Overview Products commercially available Year (Expected) Planned / Actual Revenue Products commercially available Exceeded forecast this past year 25% Profitability expected by late year

2005 Revenue by Month Year End Totals DuraSeal US Launch Total Sales

Management Team Amar Sawhney (Co-founder and CEO) Jim Fortune (COO) 24 years experience (17 with JNJ in orthopedic, neurosurgical businesses) Eric Ankerud (VP Clinical, Regulatory, Quality) 23 years experience Headed regulatory at Boston Scientific, Summit, CR Bard Patrick Campbell (VP R&D) 22 years experience (ACS, Focal)

Board of Directors Fred Khosravi (Co-founder and Chairman) Co-Founder and President, Access Closure (current), Embolic Protection, Inc., EndoTex, Inc. Sandra Panem Partner, Cross Atlantic Partners Mark Wan Founding Partner, Three Arch Partners Martin Sutter Managing Director, Essex Woodlands William Tidmore Former President, Chairman Acromed Charles Warden Versant Ventures

DuraSeal : Broad applicability and dual benefit Sealant > Cranial, Spine, Vascular, Thoracic Adhesion Barrier > Cranial, Spine, Cardiac Significant revenue opportunity Market Opportunity Neuro $$ Spine $$ Thoracic $$ Cardiac $$ Vascular $$

Confluent’s Products: Addressing Emerging Trends in Surgery Enable Minimally Invasive Surgery Provide multiple benefits: sealing, faster surgery, easier re-operations, decreased pain etc… Favorable Healthcare Economics Decrease LOS Improve Outcomes by reducing post-op complications Significant new products in emerging fields of “Biosurgery” and “Orthobiologics” Ideally suited for “combination products” that include added bioactive agents