生華科:Silmitasertib (Medulloblastoma :Fast Track Designation)/ (Cholangiocarcinoma: Orphan Drug Designation)

生華科治兒童腦瘤新藥 獲美FDA授與快速審查認定 2021年8月18日【時報記者郭鴻慧台北報導】生華科(6492)開發中新藥Silmitasertib (CX-4945)獲美FDA正式授與治療髓母細胞瘤適應症的快速審查認定(Fast Track Designation)，根據這項資格認定，生華科可以獲得美國FDA包括書面或面對面密集諮詢、滾動式審查以及具資格申請並有機會取得加速核准和優先審查。這是繼Silmitasertib在去年取得髓母細胞瘤「罕見兒科疾病認定」後，美FDA再度給與這項新藥的獎勵開發肯定，有利加速藥物及早上市。Silmitasertib進行中之髓母細胞瘤I/II期人體臨床試驗係由美國兒童腦瘤聯盟（PBTC）負責執行，並獲得美國國衛院旗下美國癌症研究中心抗癌計畫CTEP全額贊助三百萬美元經費，目前於PBTC全美旗下12所兒童醫院及癌症中心臨床進行中。由於髓母細胞瘤在美國為罕見的兒童腦瘤疾病，目前並無有效的標靶藥物治療方案，多以手術切除腫瘤後，以放射線治療腦部和脊髓，接著就是多種化療藥物治療，如幸運獲得控制，通常也會留下多重的後遺症。生華科總經理宋台生博士表示，快速審查是美國FDA為鼓勵藥廠及生技公司加速開發治療嚴重疾病或未被滿足醫療需求藥物市場所制定的加速審查機制方案之一，Silmitasertib經過審查通過並取得快速審查認定，顯見其在治療髓母細胞瘤的潛力，生華科團隊期望藥物能早日開發成功，讓病人能使用到這項新穎藥物。Silmitasertib具雙重抗癌機制，除了透過抑制人類蛋白激(酉每)CK2，阻斷癌細胞DNA修復造成癌細胞凋亡，另外藉由調控CK2，關閉下游Hedgehog (Hh)信號傳導路徑，進一步抑制癌細胞的複製生長。Silmitasertib用於治療髓母細胞瘤已於109年7月6日獲美國FDA授與「罕見兒科疾病認定」，代表未來核准上市將取得可交易的優先審查憑證(PRV)，除藥證審查期可縮短至六個月，PRV具可轉賣特性，近年交易金額也履創新高。

Medulloblastoma is the most common cancerous brain tumor in children, but no targeted therapy is currently available. On July 6, 2020, Silmitasertib was also granted Rare Pediatric Disease (RPD) Designation from the US FDA. If certain criteria are met with the RPD Designation, Senhwa is eligible for a transferrable Priority Review Voucher (PRV). The PRV allows its recipient an expedited review process of any one of its new drug products from a ten-month to a six-month timeframe.

Silmitasertib is a first-in-class small molecule drug that targets the CK2 (casein kinase 2) pathway and acts as a CK2-inhibitor. It is safe and well-tolerated in humans and is easily administered due to its oral formulation.  A Phase II Investigator-Initiated Trial (IIT) for the treatment of moderate COVID-19 recently completed enrollment, and another Phase II IIT to treat severe COVID-19 patients is currently enrolling patients in the United States. Silmitasertib is also being provided under compassionate use for patients with severe COVID-19 in Taiwan (initiated in June 2021).In addition to COVID-19, Silmitasertib is currently under development in several oncology programs in adults and children with recurrent/advanced or metastatic cancer. To date, three Phase I trials and one Phase II trial of Silmitasertib in cancer patients have been completed; currently, there are two ongoing Phase II studies of Silmitasertib in cancer patients. US FDA granted Silmitasertib an Orphan Drug Designation for the treatment of Cholangiocarcinoma in December 2016 and a Rare Pediatric Disease Drug Designation for the treatment of Medulloblastoma in July 2020.