vicky3 2009-10-26 11:36
永久的軟組織填充物Hydrogel是安全且有效的
作者：Nancy A. Melville
出處：WebMD醫學新聞
October 6, 2009（亞利桑那州鳳凰城）－根據一項發表於美國皮膚外科醫學會2009年年會上的研究結果，Hydrogel（Aquamid，Contura公司），一種永久性軟組織填充物，在治療鼻唇溝的12個月安全性及療效與常用的玻尿酸填充物Restylane（Allergan公司）相當。
Hydrogel是一種注射型的填充物，內含97.5%滅菌水與2.5%聚丙烯醯胺，且自從2001年引進後，此填充物已被核准於40個國家使用；在美國，這仍然是研究用醫材。
根據研究主要作者、紐約市紐約大學醫學中心臨床教授Rhoda Narins醫師表示，這項產品是均質的，且非具生物分解性。
她指出，這項材料具有親水性，且hydrogel與周邊組織可以持續性地交換水分；這最後將完全地以微細纖維網絡與組織融合，且不會從注射部位轉移。
在這項收納315位病患的多中心研究中，其中210位受試者接受hydrogel注射，105位接受Restylane治療。研究中容許進行兩次接觸治療，最多達三次，且以從治療前到6個月後的變化，根據皺紋評估量表（WAS）來評斷主要效果。
研究者們也評估hydrogel治療12個月後的安全性。在6個月的後續追蹤，hydrogel也被證實與Restylane一樣有效，WAS分數平均進步1.8，是事前定義臨床無顯著差異最高WAS 0.5分的三倍。
Narins醫師表示，Hydrogel的矯正可以維持12個月，且顯然沒有減弱。
她表示，最有趣的是，在12個月結束時，仍然殘留許多物質，且結果實際上仍與目前最佳治療相當。顯然的，病患們獲得的好處可以長時間維持。
Narins醫師表示，12個月時，通報的不良反應通常是輕微的，或與使用Restyland相仿。最常見的是與注射相關的反應，包括瘀青、腫脹、發紅，以及你會在其他填充物看到的事件。
Narins醫師表示，一位接受hydrogel治療的病患發生被認為與治療相關的感染；然而，該感染事件在24天內緩解。如同其他注射型填充物，感染可能與生物膜及其他問題有關。她附帶表示，醫師們應該以無菌技術並確認病患們配合治療後指示。
在hydrogel組，大約25%病患的皮膚顏色較深，且Narins醫師報告膚色較深及膚色較淺病患的療效與安全性數據是相仿的，沒有色素沉著的變化。
為了累積長期數據，一項為期24個月的試驗持續進行中，且大部分最近的數據將會支持Contura公司提報至美國食品藥物管理局對hydrogel的上市前審核。
Narins醫師指出，hydrogel要在美國核准上市最大的障礙是與大體上永久填充物有關的缺憾。進入美國市場最大的障礙就是人們害怕永久植入物。
Vivek lyengar醫師是伊利諾州芝加哥大學皮膚外科副主任，同時也是座談會的共同引言人，他同意hydrogel作為一個永久填充物面臨到更大的擔憂，只有在更長期的研究中才能充分地回答這些問題。
他表示，這項研究目前只進行第一年，當這項研究顯示hydrogel作為填充物的療效與Restylane相當時，更重要的是證明長期的安全性。
研究者們接受Contura藥廠的贊助。Narins醫師是該家藥廠的顧問以及研究者。Lyengar醫師表示沒有相關資金上的往來。
Permanent Soft-Tissue Filler Hydrogel is Safe and Effective
By Nancy A. Melville
Medscape Medical News
October 6, 2009 (Phoenix, Arizona) — Hydrogel (Aquamid, Contura), a permanent soft-tissue filler, demonstrates a 12-month safety and efficacy profile in the treatment of nasolabial folds that is similar to the popular hyaluronic acid filler Restylane (Allergan), according to a study presented here at the American Society for Dermatologic Surgery 2009 Annual Meeting.
Hydrogel is an injectable filler composed of 97.5% sterile water and 2.5% polyacrylamide, and since being introduced in 2001, the filler has been approved for use in 40 countries. It remains an investigational agent in the United States.
The product is homogenous and nonbiodegradable, according to Rhoda Narins, MD, lead author of the study and clinical professor at New York University Medical Center in New York City.
"It is hydrophilic and allows for a continuous exchange between the hydrogel and surrounding tissue," she said. "It becomes fully integrated in the tissue in a fine fibrous network and does not migrate from the injection site."
In the randomized multicenter study involving 315 patients, 210 subjects were treated with hydrogel injections and 105 were treated with Restylane. Two touch-up treatments were allowed, for a total of 3 treatments maximum, and primary effectiveness was judged by the change from baseline to 6 months, according to the Wrinkle Assessment Scale (WAS).
The researchers also evaluated the safety of hydrogel at 12 months after treatment. At 6-month follow-up, hydrogel was shown to be as effective as Restylane, offering a mean improvement in WAS score of 1.8, which is more than 3 times the maximum predefined clinically irrelevant difference of 0.5 WAS points.
The correction with hydrogel continued through 12 months without appearing to subside, Dr. Narins noted.
"The interesting thing was that at the end of the 12 months, a lot of the substance was still left and the results were in fact still as good as they were at the optimal treatment," she said. "It's clear that patients maintain this [benefit] for long periods of time."
Adverse events through 12 months were reported to be mild and similar to those that are common with Restylane, Dr. Narins said. "The most common events were injection-related and included bruising, swelling, redness, and the kinds of events you would see with most other fillers."
One patient receiving hydrogel treatments developed an infection believed to be related to the treatment; however, the infection resolved in 24 days. As with other injectable fillers, infections could be related to biofilms or other problems, Dr. Narins said. "Physicians need to use a sterile injection technique and make sure that patients adhere to post-treatment instructions," she added.
About 25% of patients in the hydrogel group had darker skin, and Dr. Narins reported that the same efficacy and safety profile was seen in both dark- and lighter-skinned patients, with no pigmentation changes.
To accumulate longer-term data, a 24-month trial is continuing, and the most recent findings will support Contura's PMA application for hydrogel with the US Food and Drug Administration.
Dr. Narins said that one of the biggest hurdles hydrogel faces in the American approval process is a stigma related to permanent fillers in general. "The biggest barrier to entry in the [American] market is that people are simply afraid of permanent fillers."
Vivek Iyengar, MD, comoderator for the session and associate director of dermasurgery at the University of Chicago in Illinois, agreed that as a permanent filler, hydrogel faces greater concerns that only longer-term studies will adequately address.
"This study was just a year, and while it did show [hydrogel] to be comparable in efficacy to a filler like Restylane, the more important proof will be its long-term safety," he said.
The researchers received funding for the study from Contura. Dr. Narins is a consultant and investigator for Contura. Dr. Iyengar disclosed no relevant financial relationships.
American Society for Dermatologic Surgery (ASDS) 2009 Annual Meeting: Abstract CS255. Presented October 2, 2009.