• IND filing today for STI-1499 (COVI-GUARD?) for hospitalized COVID-19 patients.
• The initial trial is expected to be followed by pivotal trials with a goal of potentially receiving an EUA (Emergency Use Authorization) as early as the end of this year.
• Animal model data (Syrian Golden Hamsters infected with SARS-CoV-2) confirm the neutralizing profile and high potency of this antibody, expected effective dose in human to be at least 5 times lower than current known antibodies being assessed in other active trials.
• Additional in-vitro experiments demonstrated the complete virus neutralizing property of STI-1499 against the highly contagious D614G SARS-CoV-2 variant.
• Sorrento has initiated cGMP manufacturing to produce 50,000 doses, expected to be available by the end of this year, in anticipation of a potential EUA.

SAN DIEGO,?Aug. 19, 2020?(GLOBE NEWSWIRE) --?Sorrento Therapeutics, Inc.?(Nasdaq: SRNE, ?Sorrento?) announced that it is filing an investigational new drug application (IND) for COVI-GUARD (STI-1499) for hospitalized COVID-19 patients today.

Sorrento has previously received guidance from the FDA in response to a pre-IND meeting package and believes it has addressed all questions and followed the recommendations from the agency for all sections of the IND.

As Sorrento previously announced, in preclinical studies, STI-1499 demonstrated 100% neutralizing effect (in vitro) of the antibody and that a low dose prevented SARS-CoV-2 from infecting healthy cells in such preclinical in vitro studies.

Animal data generated by Dr. Paessler?s laboratory at the?University of Texas Medical Branch at Galveston?(UTMB) in Syrian Golden Hamsters infected with SARS-CoV-2, justify the IND filing and continued clinical development. This established model, while limited, is the most predictive animal model currently available for this disease. The data were presented to federal agencies and will be published as soon as possible in a scientific journal.

The highest proposed dose (200 mg per patient) in the phase 1 safety trial is a much lower dose than currently being tested for other known antibodies in active clinical studies. The potentially higher potency of the antibody may allow for faster scaled manufacturing (availability to patients) and potentially a lower cost per dose as compared to other known antibodies currently being evaluated.

STI-1499 antibody has also been evaluated in preclinical studies against multiple strains of SARS-CoV-2, including the highly contagious D614G mutant, the current dominant strain globally. In such preclinical studies, the antibody has been 100% effective against the highly contagious D614G mutant strain at a low dose.

More information about the phase 1 clinical trial can be found on?www.clinicaltrials.gov?(NCT# 04454398).

About?Sorrento Therapeutics, Inc.? Sorrento is a clinical stage, antibody-centric, biopharmaceutical company developing new therapies to turn malignant cancers into manageable and possibly curable diseases. 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"), clinical stage immuno-cellular therapies ("CAR-T", "DAR-T?"), antibody-drug conjugates ("ADCs"), and clinical stage oncolytic virus ("Seprehvir?"). Sorrento is also developing potential coronavirus antiviral therapies and vaccines, including COVIDTRAP?, ACE-MAB?, COVI-MAB?, COVI-GUARD?, COVI-SHIELD? and T-VIVA-19?; and diagnostic test solutions, including COVI-TRACK? and COVI-TRACE?. 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 ZTlido^??(lidocaine topical system) 1.8% for the treatment of post-herpetic neuralgia. RTX is completing a phase IB trial for intractable pain associated with cancer and a phase 1B trial in osteoarthritis patients.? 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 the potency and potential blocking capabilities of STI-1499 and the impact on SARS-CoV-2; the preclinical testing of STI-1499; the safety and efficacy of STI-1499; the expectation of the commencement of any pivotal trials for STI-1499; the potential receipt of an EUA for STI-1499 and expected timing for any receipt thereof; the expected availability of doses of STI-1499 and the timing thereof; the belief that the IND addresses all questions and recommendations from the FDA; the predictive value of the animal model used in preclinical studies; the proposed dosages in the phase 1 clinical trial; the potentially faster manufacturing speed, availability and potential lower cost for STI-1499 and Sorrento's potential position in the antiviral industry. 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 and its subsidiaries', affiliates' and partners' technologies and prospects and collaborations with partners, including, but not limited to risks related to conducting pre-clinical studies and seeking IND regulatory approval for STI-1499; conducting and receiving results of clinical trials for STI-1499; the clinical and commercial success of STI-1499 against preventing and treating SARS-CoV-2 virus infections; the viability and success of STI-1499 in anti-viral therapeutic areas, including coronaviruses; 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 results may not be replicated in 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 the company in the execution of its COVID-19 therapeutic 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, 2019, 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.

Contact Alexis Nahama, DVM (SVP Corporate Development) Email:?mediarelations@sorrentotherapeutics.com

Sorrento^??and the Sorrento logo are registered trademarks of?Sorrento Therapeutics, Inc. G-MAB?, COVI-GUARD?, COVI-SHIELD?, COVIDTRAP?, T-VIVA-19?, COVI-MAB?, ACE-MAB?, COVI-TRACK?, COVI-TRACE?, COVI-MOBILE?, Saving-Life? and Improving-Life? are trademarks of?Sorrento Therapeutics, Inc.

ZTlido^??is a trademark owned by?Scilex Pharmaceuticals Inc. All other trademarks are the property of their respective owners. ? 2020?Sorrento Therapeutics, Inc.?All Rights Reserved.