whether as a result of new information, future events or otherwise. Company Overview We are a clinical-stage biotechnology company, discovering and developing novel small molecule therapeutics to treat unmet needs in aut

As used in this Exhibit 99.1, unless the context indicates otherwise, references to Kezar, the Company, we,

us, our and similar references refer to Kezar Life Sciences, Inc. and its wholly owned Australian subsidiary, Kezar Life Sciences Australia Pty Ltd.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Exhibit 99.1 contains forward-looking statements. In some cases, you can identify these statements by forward-looking words such as believe,

may, will, estimate, continue, anticipate, intend, could, should, would, potential, project, plan,

expect, seek, should, target or similar expressions, or the negative or plural of these words or expressions. These forward-looking statements include statements concerning the following:

These statements are only current predictions and are subject to known and unknown risks, uncertainties and other factors that may cause our or our

industry s actual results, levels of activity, performance or achievements to be materially different from those anticipated by the forward-looking statements. Discussions containing these forward-looking statements may be found, among other

places, in the sections titled Business, Risk Factors and Management s Discussion and Analysis of Financial Condition and Results of Operations incorporated by

reference from our most recent Annual Report on Form 10-K and most recent Quarterly Report on Form 10-Q, as well as

any amendments thereto, filed with the SEC. You should not rely upon forward-looking statements as predictions of future events.

Although we believe that

the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, levels of activity, performance or achievements. Except as required by law, we are under no duty to update or revise any of the

forward-looking statements in this Exhibit 99.1, whether as a result of new information, future events or otherwise.

We are a clinical-stage biotechnology company, discovering and developing novel small molecule therapeutics to treat unmet needs in autoimmunity and cancer.

Our lead product candidate, KZR-616, a first-in-class selective immunoproteasome inhibitor, has completed testing in healthy volunteers, and we are now leveraging its

broad therapeutic potential in three Phase 2 clinical trials across five separate autoimmune indications: lupus nephritis (the MISSION trial), autoimmune hemolytic anemia, or AIHA, immune thrombocytopenia, or ITP (the MARINA trial), dermatomyositis,

or DM, and polymyositis, or PM (the PRESIDIO trial). We are also continuing to enroll patients in the Phase 1b portion of the MISSION trial, a Phase 1b/2 clinical trial in systemic lupus erythematosus, also known as lupus or SLE, and lupus

We believe that the immunoproteasome is a validated target for the treatment of a wide variety of autoimmune diseases based on its ability to

target cells in both the adaptive and innate immune system as bolstered by compelling published activity seen with non-selective proteasome inhibitors administered to patients with severe autoimmune

diseases. Based on results from our Phase 1a studies in healthy volunteers and the preliminary results from the Phase 1b portion of the MISSION trial, KZR-616 has largely avoided adverse effects

associated with currently marketed non-selective proteasome inhibitors, as exhibited in clinical studies conducted by third parties, including side effects which we believe could prevent them from

being utilized as a chronic treatment in autoimmune disorders. We intend to develop KZR-616 to address chronic, severe and underserved autoimmune diseases.

Additionally, we are advancing our novel research platform targeting the Sec61 translocon and the protein secretion pathway to discover and develop small

molecule therapeutics targeting oncology indications. Our first clinical candidate in this program, KZR-261, has demonstrated broad anti-tumor activity in preclinical models of both solid and

hematologic malignancies. KZR-261 is undergoing laboratory studies and manufacturing activities in support of an investigational new drug, or IND, application, which we anticipate submitting to the

FDA in the first quarter of 2021 for a Phase 1 clinical trial in solid tumors. We believe this discovery platform has the potential to yield oral small molecule candidates to act as cytotoxic anti-cancer agents or to block the secretion of novel

targets of interest in immuno-oncology or inflammation and that, if successfully developed and approved, could serve as alternatives to currently marketed biologic therapeutics.

KZR-616: Selective Immunoproteasome Inhibitor

We believe that KZR-616 has potential to be developed for the treatment of multiple autoimmune disease

indications. In the last decade, research directed by our Chief Scientific Officer, along with work performed in multiple academic laboratories, has led to over 15 peer-reviewed publications showing that selective immunoproteasome inhibition

resulted in a broad anti-inflammatory response, reducing autoimmune disease in animal models of lupus, lupus nephritis, rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis, Type 1 diabetes and other indications. This

immunomodulatory response was broadly seen across many cell types of the immune system, including both T cells and B cells, and was demonstrated in a safe

and non-immunosuppressive manner. This is distinct from other agents currently used to treat autoimmunity, which typically target a single

cytokine or immune cell type or are broadly immunosuppressive.

Autoimmunity and Selective Inhibition of the Immunoproteasome

Autoimmune disease is an immune response directed against the body s own healthy cells and tissues. Approximately 50 million people in the United

States suffer from more than 100 diagnosed autoimmune diseases according to the American Autoimmune Related Diseases Association, Inc. In indications large and small, there remain significant unmet medical needs and indications with no approved

drugs beyond broadly prescribed corticosteroids and similar immunosuppressive regimens. These result in increased risk of infection and malignancy and a wide variety of side effects. In diseases such as lupus nephritis, these regimens do not induce

high rates of clinically meaningful responses.

Found in all cells of the body, proteasomes regulate intracellular protein degradation and are essential

for many cellular processes such as cell division, cell differentiation and cytokine production. There are two main forms of the proteasome: the constitutive proteasome and the immunoproteasome. In most tissues of the body, the constitutive

proteasome is the predominant form. In cells of the immune system, the immunoproteasome is the predominant form. While both forms of the proteasome mediate protein degradation, the two forms of the proteasome accomplish this utilizing different

active sites. These active sites are responsible for cleaving and degrading proteins. Selective inhibition of the immunoproteasome has the potential to reduce inflammation by targeting dysfunctional immune cells involved in autoimmunity, such as T

cells and B cells, without causing widespread immunosuppression.

Safety and Efficacy of Approved Proteasome Inhibitors

The three proteasome inhibitors approved for the treatment of multiple myeloma, Velcade (bortezomib), Kyprolis (carfilzomib) and Ninlaro (ixazomib), are

potent dual inhibitors of both the immunoproteasome and the constitutive proteasome. This dual-targeting profile is necessary to make them effective treatments for multiple myeloma. However, dual proteasome inhibition is associated with

hematologic issues such as thrombocytopenia, neutropenia and anemia, as well as constitutional toxicities such as fatigue and myalgia. In addition, Velcade and Ninlaro are associated with risk of peripheral neuropathy, likely due to the off-target activity of these drugs against proteins found in peripheral neurons.

Velcade has demonstrated

clinical activity in several autoimmune diseases, including lupus, lupus nephritis, rheumatoid arthritis, immune thrombocytopenia, autoimmune hemolytic anemia, primary Sj gren s syndrome and graft-versus-host disease. In preclinical

models, proteasome inhibition with Velcade blocked production of most inflammatory cytokines, including many of those targeted by current biologic drugs. However, long-term, chronic administration of Velcade in the setting of autoimmune diseases is

not considered feasible due to its side effect profile, in particular hematologic toxicities and risk of peripheral neuropathy. As a result, we believe that this promising drug target has remained untapped for use in the chronic treatment of

autoimmune diseases.

We believe we are the only company with a selective immunoproteasome inhibitor that is in clinical trials for the treatment of

autoimmune disorders. In addition, we believe that KZR-616, if successfully developed and approved, may have the ability to become the standard of care across a broad range of autoimmune diseases

based on the following expected key attributes:

The following table sets forth the status and initial focus of our lead product candidate and protein secretion program:

Clinical Development of KZR-616

We are focusing our initial development of KZR-616 in severe orphan autoimmune diseases where limited

treatment options exist. Currently, there are no approved treatments for lupus nephritis or AIHA in the United States or Europe, and there are limited approved treatments for DM, PM and ITP in the United States and Europe. We estimate the

addressable patient population in the United States for lupus, lupus nephritis, DM/PM and AIHA/ITP to be 460,000, 100,000 to 200,000, 70,000 and 140,000, respectively.

We currently have three active Phase 2 trials across five separate autoimmune diseases of high unmet need: the MISSION trial in patients with lupus nephritis;

the PRESIDO trial in patients with DM and PM; and the MARINA trial in patients with AIHA and ITP. Based upon the updated results from the Phase 1b portion of MISSION and the recent slowdown in recruitment and enrollment activities across our

clinical trials due to the COVID-19 pandemic, we are actively reviewing and adapting some of our clinical trial plans in order to optimize the development pathway for

KZR-616. Based on the positive safety and tolerability, pharmacology, and clinical activity results seen to date, we plan to focus future development on the 45 mg and 60 mg dose levels of KZR-616.

Phase 2 Clinical Trials

The Phase 2 portion of MISSION is intended to inform and enable late-stage clinical trials of KZR-616 in lupus

nephritis. In order to expedite the advancement of KZR-616 into the next phase of development, we plan to submit an amendment to the current clinical trial protocol in the third quarter of 2020. Based on the

data generated to date in two patients with active, proliferative LN, the primary endpoint will be changed from safety and tolerability to an efficacy endpoint of renal response measured by 50% or greater reduction in urine protein creatine ratio,

or UPCR, at six months, which has been observed to be predictive of long-term outcomes in patients with lupus nephritis. Additionally, the inclusion/exclusion criteria will be expanded to include patients with LN with histologic Class III or IV +/-

Class V being treated with current standard-of-care regardless of background therapy. The clinical trial will include a single treatment arm evaluating a 60 mg dose (with first dose of 30 mg) of KZR-616

administered subcutaneously once weekly for 24 weeks. The trial will be open-label with an opportunity for interim analyses. We expect to enroll 20 patients. Upon the successful completion of the

Phase 2 portion of MISSION, we intend to initiate a robust late-stage randomized placebo-controlled trial in patients with active, proliferative lupus nephritis.

PRESIDIO is a Phase 2 randomized, placebo-controlled, double-blind, crossover, multicenter trial to evaluate the safety, tolerability, efficacy, PK and PD of KZR-616 in patients with active PM or DM. During the 32-week treatment period, patients receive either 45 mg

of KZR-616 or placebo subcutaneously once weekly for 16 weeks followed by a crossover to the other treatment arm for an additional 16 weeks. We expect to enroll 24 patients in the trial. We believe that KZR-616 has the potential to be developed into a treatment for patients with DM and PM, which is in-part supported by preclinical data in a mouse

model of PM and DM that demonstrated immunoproteasome inhibition and improved muscle function.

MARINA is a Phase 2 randomized, dose-blind, multicenter

trial designed to evaluate the safety, tolerability, efficacy, PK and PD of KZR-616 in patients with active AIHA or ITP. In order to expedite the advancement of

KZR-616 in these orphan diseases, we plan to submit an amendment to the current clinical trial protocol in the third quarter of 2020. Under the amended protocol, patients with AIHA or ITP will receive KZR-616 subcutaneously once weekly for 13 weeks, with one dose at 30 mg and the remaining doses at 45 mg. We expect to enroll 30 patients in the trial. We believe that whole blood RNASeq data from MISSION,

which showed a decrease in multiple inflammatory gene signature and prolonged increase in erythropoietic gene signatures in SLE patients, support the broad potential anti-inflammatory activity

of KZR-616 and an application in patients with AIHA and ITP.

Phase 1 Clinical Trials

We have conducted two Phase 1a studies evaluating KZR-616 in 100 healthy volunteers. Results from these studies,

involving administration of two different formulations of KZR-616, demonstrated that KZR-616 was well tolerated in up to 75 mg (the highest tested dose).

We believe that these results support development of KZR-616 in autoimmune disorders based on the following observations:

The Phase 1b portion of MISSION is an open-label, dose escalation and dose-finding study in patients with active lupus with or without lupus nephritis who

have received at least one standard therapeutic regimen. We are evaluating doses of 45 mg, 60 mg and 75 mg. Patients receive 13 weeks of weekly subcutaneous treatment of KZR-616, followed by 12 weeks of follow-up. Cohorts 2a, 2b and 2c utilized step-up dosing to 60 mg, which was observed to improve overall tolerability. Data generated to date from the Phase 1b

portion of the MISSION trial continues to support the advancement of KZR-616 into Phase 2 trials across multiple autoimmune indications. As of the May 4, 2020 data cutoff, the Phase 1b portion

of MISSION has enrolled 39 patients across five of six cohorts. We are currently recruiting the final cohort evaluating a 75 mg dose. Results generated and released to date demonstrate that KZR-616:

Two SLE patients with biopsy-proven lupus nephritis were included in the Phase 1b portion of MISSION. Both patients showed a greater than 50% reduction in

proteinuria as measured by UPCR, as well as reductions in

Systemic Lupus Erythematosus Disease Active Index, or SLEDAI-2K, and reductions in double-stranded DNA, or anti-dsDNA, antibody levels.

Broad and consistent improvements have been seen across

multiple measures and assessments of disease activity. Among patients completing treatment, all seven measures of disease activity improved (decrease in score) in the majority of patients from Baseline to Week 13. Improvement in disease

activity has persisted following the end-of-treatment.

Below is the table of safety reporting from the Phase 1 portion of the MISSION study. Step-up dosing to 60 mg of KZR-616 has improved overall tolerability, including the mitigation of early dose effects of nausea and vomiting. Most treatment emergent adverse