Enlivex Presented Substantial Survival Benefit of Allocetra in Combination with Immune Checkpoint Inhibitor in Mesothelioma Cancer Study at the International Society for Cell and Gene Therapy Annual 2022 Meeting Mesothel

Enlivex Presented Substantial Survival Benefit

of Allocetra in Combination with Immune Checkpoint Inhibitor in Mesothelioma Cancer Study at the International Society for Cell and Gene

Therapy Annual 2022 Meeting

Nes-Ziona, Israel, May 9, 2022 (GLOBE NEWSWIRE) - Enlivex

Therapeutics Ltd. (Nasdaq: ENLV, the "Company"), a clinical-stage macrophage reprogramming immunotherapy company, announced

the poster presentation of a substantial survival benefit of AllocetraTM combined with immune checkpoint inhibition in a preclinical

mesothelioma study at the International Society of Cell and Gene Therapy Annual 2022 Meeting. The poster was titled, "Allocetra-OTS,

an Early Apoptotic Cellular Therapy Synergize with Chimeric Antigen Receptor (CAR) T Cell Therapy or Immune Check Point Inhibitor Against

Peritoneal Solid Tumor."

Mesothelioma, Treatment Landscape, and Macrophage-Solid Tumor Dynamics

Mesothelioma is one of the deadliest solid cancers with few treatment

options, all of which have limited efficacy. People who are most at risk to develop mesothelioma generally have had long-term exposure

to asbestos (e.g., construction workers, pipe fitters, and shipyard workers). It takes many years for mesothelioma to develop; it can

appear 30 years after asbestos exposure. Immune checkpoint inhibitors targeting CTLA4 and PD1 are FDA-approved as first-line treatments

for patients with unresectable malignant pleural mesothelioma.

In mesothelioma and in some other solid cancers, tumor cells, as part

of their defense mechanisms, facilitate the recruitment of macrophages which become "pro-tumor" tumor associated macrophages

(TAMs) rather than "anti-tumor" macrophages. The TAMs typically form a physical layer on top of the solid tumor, and induce

immunosuppression in the solid tumor microenvironment. This in-turn promotes tumor growth and metastasis and makes it very difficult for

the immune system or any anti-cancer drug to efficiently attack the cancerous cells. Allocetra is a cell therapy in development

that is targeted at these TAMs, and its proposed mechanism of action is to change the balance of macrophage populations to skew towards

anti-tumor macrophages and away from pro-tumor macrophages.

The Mesothelioma Model

To test the potential effect of cell therapy-induced macrophage reprogramming

on difficult-to-treat solid tumors, Enlivex ran preclinical studies in which five groups of mice were implanted with mesothelioma cancer

cells. The difference between the groups was the treatment given, which started on day 12 after the cancer's initial growth period.

Results from multiple studies strongly support the potential of AllocetraTM

to assist in the process of macrophage reprogramming in the solid tumor microenvironment and significantly change survival outcomes. As

expected, only 1/16 (6%) of the untreated mice remained alive at day 42 (that one last remaining mouse died on day 65), compared with

up to 25% survival for the mice in the group that was treated with the anti-CTLA4 immune checkpoint inhibitor. Surprisingly, AllocetraTM

as a stand-alone treatment provided comparable survival rates as anti-CTLA4 monotherapy, with a 28.5% survival rate and a delayed cancer

growth rate observed. Notably, the synergistic effect of treating with both drugs resulted in up to 100% survival with complete disappearance

of the cancer. The effect was correlated with the AllocetraTM treatment dose. A lower dose of AllocetraTM provided

slightly lower survival and cancer complete remission rates (67% complete remission for the low-dose treatment vs. up to 100% for the

higher dose). The following chart provides a visual guide to the progressions/regression of the mesothelioma cancer in the different groups,

as recorded for study mesothelioma AB12 137:

Across multiple studies of the AB12 mesothelioma model, anti-CTLA4

therapy significantly improved survival duration from mean 34 9 to 44.9 20 days (p<0.05). Allocetra as a stand-alone

therapy improved survival duration to 52.3 20 days (p<0.02). The synergistic effect of the combination therapy of anti-CTLA4

+ AllocetraTM improved survival duration to 86.7 20 days (p<0.0001) with complete cancer remission in 60-100%

of mice, depending on the dose administered.

Prof. Dror Mevorach, Chief Scientific Officer of Enlivex, stated: "This

reproducible and statistically significant data strongly support Allocetra's proposed therapeutic mechanism of action of reprogramming

macrophages in solid tumors. We believe that, in contrast to CAR-T, CAR-NK and other anti-cancer cell therapies directed at tumor antigens,

AllocetraTM restores macrophage homeostasis in the tumor environment via reprogramming of pro-tumor macrophages. This may ultimately

allow immune checkpoint inhibitors to be exponentially more effective."

Oren Hershkovitz, Ph.D., CEO of Enlivex, added: "Based on these

results, Enlivex is planning to initiate a series of clinical trials during 2022 that are designed to evaluate Allocetra in combination

with FDA-approved immune checkpoint inhibitor therapies in patients with advanced-stage solid tumors. To date, we have infused AllocetraTM

in dozens of hospitalized patients in fragile condition resulting from sepsis and COVID-19-related organ dysfunction. We believe that

the proposed differentiated mechanism of action of AllocetraTM, together with the safety and tolerability it has demonstrated

in these prior studies, as well as the encouraging efficacy results of our preclinical solid tumor models, highlight an intriguing opportunity

for Enlivex to provide another layer of life-saving therapy for patients who have few available options."

Allocetra is being developed as a universal, off-the-shelf cell

therapy designed to reprogram macrophages into their homeostatic state. Diseases such as solid cancers, sepsis, and many others reprogram

macrophages out of their homeostatic state. These non-homeostatic macrophages contribute significantly to the severity of the respective

diseases. By restoring macrophage homeostasis, Allocetra has the potential to provide a novel immunotherapeutic mechanism

of action for life-threatening clinical indications that are defined as "unmet medical needs", as a stand-alone therapy or in

combination with leading therapeutic agents.

Enlivex is a clinical-stage macrophage reprogramming

immunotherapy company developing Allocetra , a universal, off-the-shelf cell therapy designed to reprogram macrophages into

their homeostatic state. Resetting non-homeostatic macrophages into their homeostatic state is critical for immune system rebalancing

and resolution of life-threatening conditions. For more information, visit http://www.enlivex.com.

Safe Harbor Statement: This press

release contains forward-looking statements, which may be identified by words such as "expects," "plans," "projects,"

"will," "may," "anticipates," "believes," "should," "would", "could,"

"intends," "estimates," "suggests," "has the potential to" and other words of similar

meaning, including statements regarding expected cash balances, market opportunities for the results of current clinical studies and preclinical

experiments, the effectiveness of, and market opportunities for, ALLOCETRATM programs. All such forward-looking statements

are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Investors are cautioned

that forward-looking statements involve risks and uncertainties that may affect Enlivex's business and prospects, including

the risks that Enlivex may not succeed in generating any revenues or developing any commercial products; that the products in

development may fail, may not achieve the expected results or effectiveness and/or may not generate data that would support the approval

or marketing of these products for the indications being studied or for other indications; that ongoing studies may not continue to show

substantial or any activity; and other risks and uncertainties that may cause results to differ materially from those set forth in the

forward-looking statements. The results of clinical trials in humans may produce results that differ significantly from the results of

clinical and other trials in animals. The results of early-stage trials may differ significantly from the results of more developed, later-stage

trials. The development of any products using the ALLOCETRATM product line could also be affected by a number of other

factors, including unexpected safety, efficacy or manufacturing issues, additional time requirements for data analyses and decision making,

the impact of pharmaceutical industry regulation, the impact of competitive products and pricing and the impact of patents and other proprietary

rights held by competitors and other third parties. In addition to the risk factors described above, investors should consider the

economic, competitive, governmental, technological and other factors discussed in Enlivex's filings with the

Securities and Exchange Commission, including in the Company's most recent Annual Report on Form 20-F filed with the Securities

and Exchange Commission. The forward-looking statements contained in this press release speak only as of the date the statements

were made, and we do not undertake any obligation to update forward-looking statements, except as required under applicable law.

Shachar Shlosberger, CFO

Enlivex Therapeutics, Ltd.

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