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POLIDOCANOL VS STS FOR SPIDER VEINS Steven E. Zimmet, MD RPVI RVT FACPh Disclosures/COI No COI Off-label use Lipid bilayer with membrane proteins • Lipid bilayers are the basic structures that make up cell membranes. • Membrane phospholipids are amphiphilic and contain a hydrophilic polar head group and a hydrophobic tail group. Mechanism of Action Detergent sclerosants produce endothelial damage via interference with cell surface lipids Strong detergents, such as STS, produce maceration of the endothelium within 1 second of exposure. The intercellular ‘cement’ is disrupted Detergent destructive action on endothelial cells is enhanced when they act as aggregates rather than monomers. Bioactive Aggregates Critical Micellar Concentration Concentration dependent CMC of STS to be 0.075% in normal saline and 0.200% in water1 CMC of POL to be 0.002% in both normal saline and water1 Thus, the concentration of the sclerosing solution in the vessel is an important factor regarding endothelial destruction and activity STS and POL are clinically used to induce endovascular fibrosis and vessel occlusion. They achieve this by lysing the endothelial lining of target vessels. These agents are surface active (surfactant) molecules that interfere with cell membranes. The ionic charge of the surfactant molecule can influence the effect on plasma proteins and the protein contents of cell membranes. STS, an anionic detergent, denatures the tertiary complex of most proteins and in particular the clinically relevant clotting factors. By contrast, POL has no effect on proteins due to its nonionic structure. These agents therefore exhibit remarkable differences in their interaction with lipid membranes, target cells and circulating proteins with potential implications in a range of clinical applications Cell lysis reached almost 100 % with STS at 0.3 % and with POL at 0.6 %. Both sclerosants induced endothelial cell (EC) apoptosis at sub-lytic concentrations through a caspase-dependant pathway. Both agents induced EC oncosis. Cooley-Andrade et al. Apoptosis. 2016 Jul;21(7):836-45. The lytic effect of sclerosants is not limited to EC. Our group demonstrated lysis of erythrocytes, leukocytes, and platelets at concentrations specific to cell types Both sclerosants induced leukocyte apoptosis at sublytic concentrations. STS activated both extrinsic and intrinsic pathways of apoptosis, while POL stimulated the intrinsic pathway of apoptosis only. Both agents induced oncosis. Based on these results, STS appears to have a greater effect than POL. Cooley-Andrade et al. Eur J Vasc Endovasc Surg. 2016 Jun;51(6):846-56 Histological Study 40 patients after spider vein (0.8-1.0 mm diameter) treatment Punch biopsies obtained 15 minutes after treatment H&E stains Pre- and post-tx photos compared by authors regarding amount of intraluminal thrombus and hyperpigmentation Histological findings Level 1: endothelial cell destruction Level 2: subintimal disruption Level 3: fibrin replacement of vessel wall Level 4: disruption of vessel wall Bush et al. Evaluation of sodium tetradecyl sulfate and polidocanol as sclerosants for legtelangiectasia based on histological evaluation with clinical correlation. Accepted for publication in Phlebology Histological Study Histological Study Based on the histological determinations in this study, STS 0.15% and POL 0.31% appear to be equivalent in cellular alterations. The clinical effects after treatment with these two sclerosants are also similar with minimal staining and mild intraluminal thrombosis. Using concentrations less than the STS 0.15% or POL 0.31% is not as effective in producing the desired level of cellular damage. Using concentrations above these levels may produce thrombosis of vessel with resultant inflammatory changes and hyperpigmentation. Sodium Tetradecyl Sulfate (STS) Anionic surfactant Nonmutagenic when tested in a mouse lymphoma assay, but no long-term animal carcinogenicity studies have been performed FDA-approved 1946 Commercially available preparations as1% or 3% solutions Indicated in the treatment of small uncomplicated varicose veins of the lower extremities that show simple dilation with competent valves Sotradecol should be given to a pregnant woman only if clearly needed and the benefits outweigh the risks It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when Sotradecol is administered to a nursing woman. Maximum single treatment should not exceed 10 mL. Can be readily made into foam (physician-compounded) Polidocanol (POL) Non-ionic detergent, consisting of two components, a polar hydrophilic (dodecyl alcohol) and an apolar hydrophobic (polyethylene oxide) chain. FDA-approved 2010 Asclera (polidocanol) indicated to treat uncomplicated spider veins (varicose veins ≤1 mm in diameter) and uncomplicated reticular veins (varicose veins 1 to 3 mm in diameter) in the lower extremity. It has not been studied in larger varicose veins > 3 mm in diameter. Maximum 10 mL/session Severe allergic reactions have been reported following polidocanol use, including anaphylactic reactions, some of them fatal. Severe reactions are more frequent with use of larger volumes (> 3 mL). The dose of polidocanol should therefore be minimized. Be prepared to treat anaphylaxis appropriately. It is not known whether polidocanol is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants, avoid administering to a nursing woman. Can readily made into foam (physician-compounded), commericially available as Varithena (GSV) Clinical Pharmacology Mechanism of Action Damages endothelium Dense network of platelets, cellular debris and fibrin occludes the vein Pharmacodynamics Concentration and volume-dependent Pharmacokinetics The mean plasma half life (4 subjects) who received 4.5 to 18.0 mg polidocanol was 1.5 hours. These are far greater mg dosages than would be reached in a typical clinical setting. Maximum recommended volume per treatment session of 10 mL. Polidocanol has been shown to have an embryocidal effect in rabbits when given in doses approximately equal (on the basis of body surface area) to the human dose. This effect may have been secondary to maternal toxicity. There are no adequate and wellcontrolled studies in pregnant women. Asclera should not be used during pregnancy. STS & POL are deactivated by blood proteins1,2 Conner et al3 found detergent sclerosants are also deactivated by circulating blood cells. This deactivating effect is above and beyond the neutralizing effects of plasma proteins and contributes to the overall neutralizing effect of blood. At high enough concentrations, surfactants solubilise cell membranes resulting in cell lysis. In Vitro study: endothelial cell lysis at STS .25% and POL 0.4%2 Watkns. European Journal of Vascular & Endovascular Surgery 2011;41(4):521-525. Parsi et al. Eur J Vasc Endovasc Surg (2008) 36, 216e223. Samples of whole blood, platelet-rich plasma, and isolated leukocytes were incubated with various concentrations of STS or POL and added to human umbilical vein endothelial cells Detergent sclerosant activity was decreased in WB when compared with plasma and saline controls Detergent sclerosants are consumed and deactivated by circulating blood cells. This deactivating effect is above and beyond the neutralizing effects of plasma proteins and contributes to the overall neutralizing effect of blood. Connor et al. Eur J Vasc Endovasc Surg (2015) 49, 426e431 Liquid Detergent Sclerosants & Endothelial Cell Death Cell cultures of bovine aortic endothelial cells Continuous exposure to varying concentrations of Pol (0.003-1.5%) and STS (0.005-0.5%) Fluorescence imaging every 2-6 seconds for up to 60 minutes to assess: Intracellular calcium Nitric oxide Cell death Kobayashi et. al. Derm Surg 2006;32(12):1444-52. Liquid Detergent Sclerosants & Endothelial Cell Death Time to response for all markers was inversely related to sclerosant concentration STS 0.5% STS 0.1% STS 0.02% STS 0.005% 15 seconds to cell death 3.5 minutes to cell death 15 minutes to cell death no cell death Appeared to be sequential activation of Calcium-dependent pathways Nitric oxide production Followed by rapid progression to cell death French POL Study 12 physicians- Data on 1,605 patients included in the French registry were reviewed with a maximum followup of 60 months, covering 3,357 patient years. Most of the sessions were performed with sclerosants in foamed formulation (n = 4,403); the rest (n = 2,041) was performed with liquid sclerosants. French Study Australian POL study 98 physicians, 16804 limbs, results at 2 years 65 Investigators utilized polidocanol and compared it to their previous use of other sclerosants 0.5-1.0% for spider veins 85% felt POL superior to STS 90% felt fewer complications Conrad et al. Derm Surg 1995;25:334-6. Goldman RCT 129 pts w/o related underlying reflux Spider veins, reticular veins, varicose veins Spiders: .25% STS or .5% POL 3 Independent blinded photo reviewers at 4 and 16 wks Both groups average 70% improvement Similar side effect rate EASI Study Double blind, randomized prospective study Spider veins (n=160) 0.5% Pol 1% STS placebo Reticular veins (n=156) 1% Pol 1% STS placebo Rabe et al. Phlebology. 2010 Jun;25(3):124-31s Treatment Success Rates Treatment Success* Rated by blinded panel Defined as grade 4 0r 5 (good or complete success) No difference between Pol and STS *Treatment success was rated on a 5-point scale: 1 = worse than before 2 = same as before 3 = moderate improvement 4 = good improvement 5 = complete treatment success Patient Satisfaction Patients Satisfied/Very Satisfied 100% 80% 60% Patient Satisfaction rated on 1-5 scale (% reflects patients satisfied or Asclera (0.5% or 1%) STS (1%) very87% satisfied) 84% ® Placebo (0.9% isotonic saline) 64% 63% 40% 20% 14% 16% 0% 12 weeks 26 weeks P<0.0001 for all comparisons Complications 80% 70% 60% 50% STS POL 40% 30% 20% 10% 0% Pigmentation Necrosis Matting Actually, Too POL highconcentration a concentration (0.5/1.0 %) also too high of STS (1%) Complications 80% 70% 60% 50% Used too high a concentration of STS STS POL 40% 30% 20% 10% 0% Pigmentation Necrosis Matting Rabe et al. Phlebology. 2010 Jun;25(3):124-31 Spider vein: HS vs POL Non-randomized study in 113 consecutive patients HS POL .5 % POL 1 % Pigmentation 10.8% 20% 30.7% Matting 13 % 10% 33% POL concentration probably too high Weiss and Weiss. Derm Surg 1990, 16(9):800-4. Liquid vs Foam Spider veins: Higher incidence pigmentation, ulceration1 French POL Study2: “We recommend the use of liquid polidocanol for treatment of spider, reticular, and small varicose veins” Liquid treatment of choice in C1 patients3 1. 2. 3. Kern et al. Derm Surg. 2004 Mar;30(3):367-72 Guex et al. Derm Surg 2010;36:S2:993-1002. Rabe et al. European guidelines. Phlebology, Sclerosant: Liquid vs Foam RCT: 75 pts (69 women) served as their own control Reticular or post-op varices 1 session: POL liquid or foam Concentration adjusted based on vein size [Foam] 50% lower than liquid Eur J Vasc Endovasc Surg. 2006 Jan;31(1):101-7. Sclerosant Concentration The key is to deliver a minimum sclerosant volume & concentration to irreversibly damage the endothelium & cause complete sclerosis, without collateral damage. Spider Veins Reticular Veins Varicose Veins HS 11.7 – 23.4% n/a n/a D/ S FS (25%/10%) n/a n/a G 72% n/a n/a Pol .25-.5% .5 - 1% 1 - 3% STS .1 - .2% .2 - .5% .33 – 3% Cost of FDA-Approved Agents Sotradecol Cost/mL Asclera Cost/mL 1% $57 .5% $10 3% $63 1% $11 .15% $3.13 .25% $3.33 Compounded Sclerosants 1% Polidocanol concentrations ranged 1-3%, and impurities found1 STS 3% concentrations ranged 2.59%-3.39% and carbitol present in samples from all three sources (0.33%-4.18%)2 Weiss et al. Dermatol Surg. 2011 Jun;37(6):812-5. Goldman. Dermatol Surg. 2004 Dec;30(12 Pt 1):1454-6. Compounding: Ask Yourself Is an FDA-approved version available? Do you inform your patients you’re using a compounded version as a substitute for an FDA-approved medication? Why are you using a compounded product when an FDA-approved version exists? If compounded drug determined to be the cause of a negative, preventable outcome, the physician may be liable for selecting the compounded drug Think New England Compounding Center