Allogeneic Natural Killer Cells Engineered to Beat Cancer

November 2019 Investment highlights: Nkarta engineered CAR-NKs

Natural Killer cells are the cornerstone of innate immune surveillance Targeting OX40 » Allogeneic and off-the-shelf with CD3ζ attractive COGS CAR » Proprietary expansion, persistence, cryopreservation and tumor targeting technologies CAR-NK Cell mbIL-15 » Three clinical programs in next ~12 months Targeting receptor, OX40 costimulatory domain, CD3ζ signaling moiety, » $114M Series B with top healthcare membrane bound IL-15 investors

INDICATION DISCOVERY PRECLINICAL IND PHASE 1

AML and MDS (systemic i.v.) 1Q20 2Q20 NKX101 (NKG2D) HCC/mCRC/ICC (locoregional i.a.) 2Q20 3Q20

NKX019 (CD19) B-cell malignancies 3Q20 4Q20

PROGRAM 3 Not disclosed 2021 2021

NK + T Not disclosed 2022 2022

i.v.: intravenous (systemic) administration; i.a.: intra-arterial (locoregional) administration

© 2019 Nkarta Therapeutics. 3 Extensive clinical experience validates NK approach Patients have been treated with non- MD Anderson study with CD19 CAR-NK cells engineered NK cells across ~30 studies ü 7 / 11 CRs in patients with advanced B-cell malignancies Well tolerated and no GvHD ü No cytokine release syndrome, GvHD or neurotoxicity (non-transplant) ~600 Patients treated with non-engineered PRE-ADMISSION DAY 30 POST CAR NK allogeneic NK cells ~400 AML/MDS Patient #6 – patients achieved CR. CAR NK cells ~100 traffic to sites R/R AML of disease (non-transplant)

~34% aggregate CR rate

Sources: Velluchamy 2017; Nkarta systematic literature review; Rezvani TCT 2019 and ASGCT 2019

Expansion Cryopreservation Persistence Targeting

Co-culture with Maintains NK viability Expression of Engineered for stimulatory cell line to and potency membrane bound IL-15 expression of CARs and achieve high cell doses to enhance time in bispecifics circulation

APPROVED ALLO CAR-T CAR-T NK NKARTA THERAPIES THERAPIES CELLS CAR-NK DISCRIMINATE HEALTHY VS. CANCER CELLS PP TARGETS OVEREXPRESSED IN MANY TUMOR TYPES PP POTENTIAL SYNERGY WITH CHECKPOINT INHIBITORS P PPP LOW GVHD RISK P TBD PP OFF-THE-SHELF MANUFACTURING P P PERSISTENCE PP P P

Nkarta’s platform generates CAR-NKs designed to address the limitations of current CAR-T therapies, including safety, manufacturing time, COGS, and GVHD risk

In vitro persistence In vivo persistence and expansion in NSG mice 20 400 Non-engineered NK cells NonUnmodified-engineered NK cells NK cells NK cells expressing mbIL-15 NKNK cells cells expressing expressing mbIL mbIL-15-15 (NKX101) NK cells expressing soluble IL-15

300 15

200 10

100 5 % Cell Recovery Cell % % of totalPBMCs of %

0 0 7 14 21 28 35 42 49 56 63 7 14 21 28 35 Days of Culture Days

Source: Imamura, Blood 2014 Source: Nkarta. N = 5 per arm.

NK cells engineered to express membrane-bound IL-15 (mbIL-15) demonstrate superior persistence as compared to unmodified NK cells

GFP- NKG2D-CAR Control expressing NKG2D-CAR + mbIL-15 1.2×1010 Control (PBS) NK cells NK cells NK cells GFP-expressing NKs NKG2D-CAR NKs Day 7 1×1010 NKG2D-CAR + mbIL-15 NKs

Day 14 8×109

Day 21 6×109

Day 28 4×109 Post tumor Day 35 BLI (photon/sec) 2×109 Day 49

0 Day 63 7 14 21 28 35 49 63 Time (days) Source: Nkarta. U2OS osteosarcoma model; 3 x 106 NK cells administered on D7. Graphical data at right are average BLI of mice above. NK cells demonstrate enhanced tumor killing when engineered for targeting and mbIL-15 expression

1 Collect & Isolate 2 Activate 3 Engineer 4 Expand 5 Cryopreserve 6 Thaw & Administer

NK cell

Stimulatory cell line g-retro-virus

NK cells collected from NK cell expansion using Expanded NK cells are Continued expansion Harvesting and NK product candidate healthy donors by proprietary stimulatory transduced to express driven by mbIL-15. cryopreservation of is thawed for off-the- leukapheresis. cells. mbIL-15 and CAR. final cell product. shelf administration to patients.

Average doses generated (Projected) » Expansion technology used in 6 1000 681 clinical trials (non-engineered NKs) » Extensive optimization enables 100 64 truly off-the-shelf products

10 » Projected COGS at peak

NumberDoses of <$2,000 / dose

1 » Building out in-house GMP 0 7 14 Days of Expansion manufacturing suite

Data above are an average of 62 expansions from 18 different donors. Assumed dose is 109 CAR-NK cells, the highest contemplated in the NKX101 heme Phase 1 trial.

» NK activation and tumor killing largely driven by NKG2D receptor NKG2D OX40 CD3ζ » >10x increase in NKG2D expression CAR vs. non-engineered NK cells » OX40 selected based on superiority vs. other costimulatory domains mbIL-15 » Targets of NKG2D are selectively over-expressed in cancer cells NKX101: NKG2D activating receptor, OX40 costimulatory domain, CD3ζ signaling moiety, membrane bound IL-15

NKG2D ligand expression is documented Clinical responses observed in R/R AML with in multiple tumor types non-engineered allo-NKs validate NKG2D

TUMOR TYPE REFERENCE STUDY RESPONSES* AML, ALL, CML, CLL Hilpert, J Immunol 2012 Bachanova, Crit Rev Oncog 2014, A+B cohort 9 / 42 (21%) MULTIPLE MYELOMA Carbone, Blood 2005 Bachanova, Crit Rev Oncog 2014,C cohort 8 / 15 (53%) HCC Kamimura, J Hep 2012 Curti, Blood 2011 1 / 5 (20%) BREAST de Kruif, BMC Can 2012 Kottaridis, PLOS One 2015 1 / 1 (100%) OVARIAN McGilvray, Int J Can 2010 Miller, Blood 2005 5 / 19 (26%) LUNG Okita, Can Imm Immunother 2016 Romee, Sci Transl Med 2016 5 / 9 (57%) COLON McGilvray, CCR 2009 Rubnitz, Pediatr Blood Cancer 2015 6 / 12 (50%) MELANOMA Vetter, J Inv Derm 2002 OVERALL 35 / 103 (34%) OSTEOSARCOMA Lu, Neoplasma 2008 *AML responses in patients with morphologic disease at baseline as reported in individual trials, patients with CR at study entry excluded from summary. The GLIOMA Weiss, CCR 2018 35 responses include 20 CR, 12 CRi, 2 CRp and 1 MLFS.

GFP- » AML US incidence: ~20K / yr expressing NKX101 NKX101 NKX101 6 7 7 • 5-year survival rate ~27% NK cells (5 x 10 cells) (1 x 10 cells) (2 x 10 cells) Day 6 » NKG2D targets are over-expressed in AML blasts Day 12

» Clinical activity with non- Day 18 engineered NKs Day 24 » Positive pre-IND meeting Post tumor Day 30 May 2019 » Phase 1 in r/r AML and high-risk Day 36 THP-1 xenograft model treated with a single dose of NK cells (i.v.) MDS to open 2Q20 2 days after tumor injection

Sources: SEER database; Veluchamy, Front Immunol 2017; Brayer ASH 2018; Hilpert, J Immunol, 2012

Dose finding (3+3 design, 3 cohorts, 108 / 3x108 / 109 CAR-NK cells / dose) Pre-treatment (~25 days) Cycle one (28 days) Cycle two (28 days)

Leuka- Haplomatched donor pheresis Manufacturing NKX101 Mfg. Second cycle TBD & Release Trial subject Conditioning Dosing d0 / d7 / d14 Conditioning Dosing d0 / d7 / d14

Dose expansion (12 patients, the half with unrelated donor shown below) Pre-treatment (4 days) Cycle one (28 days) Cycle two (28 days) Second cycle TBD

Trial subject Conditioning Dosing d0 / d7 / d14 Conditioning Dosing d0 / d7 / d14

Half the subjects in the dose expansion cohort will be treated with previously manufactured, off-the-shelf NKX101 – the same as our expectation for pivotal trials and commercial use

» HCC US incidence: ~30K / yr NKX101 activity in NSG mice • 5-year survival rate ~18% PBS control GFP-expressing NKs NKX101

» NKG2D targets over-expressed Day 7 on HCC and CRC cells Day 14 » NK cells are important in liver immunity and tumor surveillance Day 21 Post tumor » Activity of non-engineered NK cells Day 28 in HCC/ICC: 3/16 PRs Day 35 » Phase 1: Locoregional delivery SNU449 HCC xenograft model using SOC technique in 1° 3 x 106 NK cells injected at day 7 post-tumor liver cancer or liver metastases

Sources: SEER database; Sun Act Pharm Sin 2015; Kamimura, J Hepatology, 2012; Kamiya et. al, Cancer Immunol Res 2016; Qin 2017

• Gr3+ neurotoxicity: 18–31% CD19 binder OX40 • Limited number of specialized sites can treat CD3ζ • 23–34% of patients in Kymriah pivotals didn’t CAR receive cells (primarily due to mfg. time) » Rezvani (MDACC / Takeda) CAR19-NK: • 7/11 CRs in CLL / DLBCL / Follicular

(avg. 5 prior rounds Tx) mbIL-15 • No CRS, GvHD or neurotoxicity » Compelling commercial opportunity: NKX019: Proprietary CD19 binder, OX40 costimulatory domain, CD3ζ signaling • Allogeneic off-the-shelf product with low COGS moiety, membrane bound IL-15 • Clean safety profile Sources: Kymriah and Yescarta package inserts; Rezvani presentation at ASGCT April 2019

MANAGEMENT TEAM BOARD

Paul Hastings Ali Behbahani, MD President & CEO Chairman

Ralph Brandenberger, PhD Tiba Aynechi, PhD VP, Development & Manufacturing Director

Nadir Mahmood, PhD Fouad Azzam, PhD Chief Business Officer Director

Matthew Plunkett, PhD Jill Carroll Chief Financial Officer Director

Kanya Rajangam, MD, PhD Mike Dybbs, PhD Chief Medical Officer Director

James Trager, PhD Paul Hastings Chief Scientific Officer Director

PLATFORM NKX101 NKX019 NK cell expansion NKG2D target CD19 » Multiple issued patents and » Issued US patent and multiple » Provisional applications pending applications pending US/OUS/PCT applications » Cells expressing tumor-targeting » Compositions and methods » Claims to various NKG2D targeting receptor & cytotoxic effector of expansion/treatment constructs & treatment methods » Expiry ~2040 » Expiry ~2024 to ~2038 » Expiry ~2034–2039 NK cell persistence Local NKX101 delivery » Allowed US application and » Provisional applications multiple pending OUS » Local delivery to tumors applications » Expiry ~2039 » Expiry ~2035 Combo Therapy Pipeline » Provisional applications » Provisional applications » NKG2D construct + adjunct therapy » Compositions & treatment » Expiry ~2039 methods » Expiry ~2039 to 2040

» Samsara BioCapital led $114 million Series B financing (August 2019) » Nkarta is capitalized into late 2021: post-POC for NKX101 and NKX019 » Leading investor syndicate

2019 2020 2021

Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4

IND Enabling IND Start-up Ph1 dose finding: Heme R/R AML exp.

NKX101 (NKG2D)

IND Enabling IND Start-up Ph1 dose finding: Solid Tumors HCC/mCRC exp.

NKX019 (CD19) IND Enabling IND Start-up Ph1 dose finding: B-Cell malignancies

Clinical GMP In-House Pivotal / Commercial GMP In-House

GMP Facilities Design Build Qualif. Design Build