Sorrento Therapeutics Announces China National Medical Products Administration (NMPA) IND Clearance of STI-1558, An Oral Mpro Inhibitor for Phase I Trial In COVID-19 Patients

• STI-1558, an oral SARS-CoV-2 main protease (M^pro) inhibitor, which can block viral replication, is specifically designed as a standalone treatment of COVID-19 without ritonavir as a booster.
• Single ascending dose (SAD) portion of the Phase I healthy subject study has been completed in Australia with the maximum dose of 2,000 mg. There were no serious adverse events (SAEs) or severe treatment emergent adverse events (TEAEs), and pharmacokinetics (PK) were dose proportional.
• In the NMPA-cleared China Phase I trial, STI-1558 will be given to subjects with COVID-19 in multiple ascending doses (MAD) with three dose cohorts, including 300 mg BID, 600 mg BID and 800 mg BID, to evaluate safety, tolerability and efficacy, to be conducted in parallel to the MAD portion of the study in healthy subjects in Australia.

SAN DIEGO, Aug. 19, 2022 (GLOBE NEWSWIRE) — Sorrento Therapeutics, Inc. (Nasdaq: SRNE, “Sorrento”) today announced the NMPA clearance of a Phase I study of its oral main viral protease (M^pro) inhibitor, STI-1558, in subjects with COVID-19 in a MAD study in China.

In a previously announced Australia Phase I study in healthy subjects, the SAD portion with four dose cohorts (300 mg, 600 mg, 1200 mg, and 2000 mg) has been completed. The MAD portion of the study is starting and STI-1558 has been well tolerated to date with only a few related adverse events, which have been transient and mild in severity. The PK profile has matched the predicted values based on the animal studies and confirms that STI-1558 is readily absorbed by humans with high bioavailability and no need for ritonavir, a potent cytochrome P450 3A4 inhibitor, to block metabolic clearance in order to maintain effective blood levels. In the NMPA cleared Phase I trial, STI-1558 will be administered to subjects with COVID-19 with mild or no symptoms in this MAD study, allowing for an evaluation of the safety, tolerability and efficacy of STI-1558 as a standalone treatment without ritonavir as a booster.

In the double blind and placebo-controlled MAD study, a total of 56 patients with mild or no symptoms will be enrolled into three dose cohorts (active: placebo, 3:1), 300 mg BID (n=8), 600 mg BID (n=24) and 800 mg BID (n=24). In addition to evaluation of the safety and tolerability, the viral load in patients will be examined to assess the antiviral activity of STI-1558 treatment in subjects with COVID-19 in comparison with placebo treatment. The trial will support seeking approval for an Emergency Use Authorization (EUA) in China and will be conducted by ACEA Therapeutics, Inc., a Sorrento company, and the Third Shenzhen Hospital in Shenzhen China. Dr. Lu Hangzhou, Professor and Fellow of American Academy of Microbiology, and President of The Third Shenzhen Hospital, is leading the trial in China.

“The trial in China will allow us to evaluate STI-1558 antiviral activity in patients together with safety, tolerability and pharmacokinetics in different dose levels. We are looking forward to seeing the results in COVID-19 patients, which we expect to facilitate our planned STI-1558 Phase II/III trials in Mexico and the U.S.,” stated Henry Ji, Ph.D., President and CEO of Sorrento.

About Sorrento Therapeutics, Inc. 

Sorrento is a clinical and commercial stage biopharmaceutical company developing new therapies to treat cancer, pain (non-opioid treatments), autoimmune disease and COVID-19. Sorrento’s multimodal, multipronged approach to fighting cancer is made possible by its extensive immuno-oncology platforms, including key assets such as fully human antibodies (“G-MAB™ library”), immuno-cellular therapies (“DAR-T™”), antibody-drug conjugates (“ADCs”), and oncolytic virus (“Seprehvec™”). Sorrento is also developing potential antiviral therapies and vaccines against coronaviruses, including Abivertinib, COVISHIELD™ and COVI-MSC™; and diagnostic test solutions, including COVIMARK™.

Sorrento’s commitment to life-enhancing therapies for patients is also demonstrated by our effort to advance a first-in-class (TRPV1 agonist) non-opioid pain management small molecule, resiniferatoxin (“RTX”), and SP-102 (10 mg, dexamethasone sodium phosphate viscous gel) (SEMDEXA™), a novel, viscous gel formulation of a widely used corticosteroid for epidural injections to treat lumbosacral radicular pain, or sciatica, and to commercialize ZTlido^® (lidocaine topical system) 1.8% for the treatment of postherpetic neuralgia (PHN). RTX has been cleared for a Phase II trial for intractable pain associated with cancer and a Phase II trial in osteoarthritis patients. Positive final results from the Phase III Pivotal Trial C.L.E.A.R. Program for SEMDEXA™, its novel, non-opioid product for the treatment of lumbosacral radicular pain (sciatica), were announced in March 2022. ZTlido® was approved by the FDA on February 28, 2018.

For more information visit www.sorrentotherapeutics.com

Forward-Looking Statements

This press release and any statements made for and during any presentation or meeting contain forward-looking statements related to Sorrento Therapeutics, Inc., under the safe harbor provisions of Section 21E of the Private Securities Litigation Reform Act of 1995 and subject to risks and uncertainties that could cause actual results to differ materially from those projected. Forward-looking statements include statements regarding STI-1558, including the potential antiviral profile of STI-1558 with respect to SARS-CoV-2 and its variants; the preclinical testing of STI-1558; the potential safety and efficacy of STI-1558; the potential that no co-administration will be required with STI-1558; the oral bioavailability of STI-1558; the potential success of the Phase I trials in Australia and China; the Phase II/III trials in Mexico and the U.S.; the potential for the trial to assist in seeking EUA approval in China; STI-1558’s and Sorrento’s position in the antiviral industry; the expected formulation, dosing and/or route of administration for STI-1558; and the preparation of a global commercial supply of STI-1558. Risks and uncertainties that could cause our actual results to differ materially and adversely from those expressed in our forward-looking statements, include, but are not limited to: risks related to Sorrento’s technologies and prospects, including, but not limited to risks related to safety and efficacy of STI-1558 and seeking regulatory approval for STI-1558; clinical development risks, including risks in the progress, timing, cost, and results of clinical trials and product development programs; risk of difficulties or delays in obtaining regulatory approvals; risks that clinical study results may not meet any or all endpoints of a clinical study and that any data generated from such studies may not support a regulatory submission or approval; risks that prior test, study and trial results, including PK modeling and values obtained therefrom, may not be replicated in continuing or future studies and trials; risks of manufacturing and supplying drug product; risks related to leveraging the expertise of its employees, subsidiaries, affiliates and partners to assist Sorrento in the execution of its product candidates’ strategies; risks related to the global impact of COVID-19; and other risks that are described in Sorrento’s most recent periodic reports filed with the Securities and Exchange Commission, including Sorrento’s Annual Report on Form 10-K for the year ended December 31, 2021 and subsequent Quarterly Reports on Form 10-Q filed with the Securities and Exchange Commission, including the risk factors set forth in those filings. Investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this release, and we undertake no obligation to update any forward-looking statement in this press release except as required by law.

Media and Investor Relations
Contact: Brian Cooley
Email: mediarelations@sorrentotherapeutics.com

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