8-K - PDSB - Equibles

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 8, 2024

PDS BIOTECHNOLOGY CORPORATION

(Exact Name of Registrant as Specified in Charter)

Delaware	001-37568	26-4231384
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(I.R.S. Employer Identification No.)

303A College Road East,

    Princeton, NJ 08540

(Address of Principal Executive Offices, and Zip Code)

(800) 208-3343

Registrant’s Telephone Number, Including Area Code

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the

  following provisions \(see General Instruction A.2. below\):

☐	Written communication pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
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☐	Pre-commencement communication pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
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☐	Pre-commencement communication pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
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Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading Symbol(s)	Name of each exchange on which<br><br> <br>registered
Common Stock, par value $0.00033 per share	PDSB	The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. Yes ☐ No ☐

Item 8.01	Other Events.

On May 8, 2024, PDS Biotechnology Corporation updated its corporate presentation deck. A copy of the corporate presentation is filed as Exhibit 99.1 and incorporated herein by reference.

Item 9.01	Financial Statements and Exhibits.

(d) Exhibits.

Exhibit<br><br> <br>Number	Description
99.1	Corporate Presentation (May 2024).
104	Cover Page Interactive Data File (embedded within the Inline XBRL document).

Signature

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	PDS BIOTECHNOLOGY CORPORATION
Date: May 8, 2024	By: /s/ Frank Bedu-Addo, Ph.D.
	Name: Frank Bedu-Addo, Ph.D.
	Title: President and Chief Executive Officer

Exhibit 99.1

Forward-Looking Statement This communication contains forward-looking statements (including within the meaning of Section 27E of the United States Securities Exchange Act of 7934, as amended, and Section 27A of the United States Securities Act of 7933, as amended) concerning PDS Biotechnology Corporation (the "Company") and other matters. These statements may discuss goals, intentions and expectations as to future plans, trends, events, results of operations or financial condition, or otherwise, based on current beliefs of the Company's management, as well as assumptions made by, and information currently available to, management. Forward-looking statements generally include statements that are predictive in nature and depend upon or refer to future events or conditions and include words such as "may" "will" "should" "would" "expect" "anticipate" "plan" "likely" "believe" "estimate" "project“ "intend," "forecast," "guidance", "outlook" and other similar expressions among others. Forward-looking statements are based on current beliefs and assumptions that are subject to risks and uncertainties and are not guarantees of future performance. Actual results could differ materially from those contained in any forward-looking statement as a result of various factors, including, without limitation: the Company's ability to protect its intellectual property rights; the Company's anticipated capital requirements, including the Company's anticipated cash runway and the Company's current expectations regarding its plans for future equity financings; the Company's dependence on additional financing to fund its operations and complete the development and commercialization of its product candidates, and the risks that raising such additional capital may restrict the Company's operations or require the Company to relinquish rights to the Company's technologies or product candidates; the Company's limited operating history in the Company's current line of business, which makes it difficult to evaluate the Company's prospects, the Company's business plan or the likelihood of the Company's successful implementation of such business plan; the timing for the Company or its partners to initiate the planned clinical trials for PDS01ADC, PDS0101 and other Versamune® and lnfectimune® based product candidates; the future success of such trials; the successful implementation of the Company's research and development programs and collaborations, including any collaboration studies concerning PDS01ADC, PDS0101 and other Versamune® and lnfectimune® based product candidates and the Company's interpretation of the results and findings of such programs and collaborations and whether such results are sufficient to support the future success of the Company's product candidates; the success, timing and cost of the Company's ongoing clinical trials and anticipated clinical trials for the Company's current product candidates, including statements regarding the timing of initiation, pace of enrollment and completion of the trials (including the Company's ability to fully fund its disclosed clinical trials, which assumes no material changes to the Company's currently projected expenses), futility analyses, presentations at conferences and data reported in an abstract, and receipt of interim or preliminary results (including, without limitation, any preclinical results or data), which are not necessarily indicative of the final results of the Company's ongoing clinical trials; any Company statements about its understanding of product candidates mechanisms of action and interpretation of preclinical and early clinical results from its clinical development programs and any collaboration studies; to aid in the development of the Versamune® platform; and other factors, including legislative, regulatory, political and economic developments not within the Company's control. The foregoing review of important factors that could cause actual events to differ from expectations should not be construed as exhaustive and should be read in conjunction with statements that are included herein and elsewhere, including the risk factors included in the Company's annual, quarterly and periodic reports filed with the SEC. The forward-looking statements are made only as of the date of this press release and, except as required by applicable law, the Company undertakes no obligation to revise or update any forward-looking statement, or to make any other forward-looking statements, whether as a result of new information, future events or otherwise. Versamune® and lnfectimune® are registered trademarks of PDS Biotechnology Corporation. KEYTRUDA® is a registered trademark of Merck Sharp and Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.

Late-Stage Head and Neck Cancer Program as Value Catalyst 1. Company’s 10-K for year ended 12/31/2023 includes going concern opinion. Cash runway estimate based on currently available cash resources and cash flow projections and assumes no initiation of pivotal trial and Company debt not being called by lenders. High-Value Lead Program Novel Investigational “Inside-Outside” MOA Robust Phase 2 Data in 400+ Patients Financials Pivotal trial planned for PDS01ADC + Versamune® HPV (PDS0101) + pembrolizumab in first line recurrent/metastatic head and neck cancer in 2024 PDS01ADC + Versamune® disrupts tumor’s inside defenses, and generates potent, targeted killer T-cell attack from outside Compelling Phase 2 survival data PDS01ADC favorable safety profile demonstrated in >300 patients Versamune® HPV administered to >110 HNSCC patients Cash runway into Q4 2025 (without pivotal trial)1

Two Critical Limitations Remain References: Darvin et al. Experimental & Molecular Medicine (2018) 50:165. Chen, D. S. & Mellman, I. Nature 541, 321 (2017). Why Immunotherapies Fail in Solid Tumors Immune-Desert Tumors: Lack T cells because T cells don’t get activated or recognize the cancer Immune-Excluded Tumors: Contain immune suppressive cytokines and inhibitory factors that prevent T cell infiltration TME = Tumor Microenvironment TME Prevents Immunogenicity Inability to generate the right type and quantity of effective tumor-infiltrating and tumor-killing T cells Inadequate T Cell Response

Potential to Overcome Suppression of the T Cell Response by the Tumor TME = Tumor Microenvironment Proprietary Dual Platform Enables Inside-Outside Attack on Tumor NHS76 (Tumor Necrosis Targeting Ab – Binds to exposed DNA) De-immunized Junction IL-12 (p40 clipping-resistant) IL-12 (p40 clipping-resistant) IL-12 fused antibody drug conjugate Water-insoluble fatty acids/ hydrocarbon chains Water-soluble, positively charged head-group coats particle surface Immunologically active R-enantiomer of 1,2-dioleoyl-trimethyl-ammonium (R-DOTAP) Inside Infiltrates TME to Suppress the Tumor’s Defenses & Promotes T Cell Infiltration/Immunogenicity Outside PDS01ADC Most clinically advanced tumor-targeted IL-12 Versamune® Outside Induces Right Type & Quantity of Powerful Tumor-Targeting Killer T Cells

VERSATILE-002 Phase 2 Clinical Trial (Multi-Site US/EU Trial) Objective: To Assess the Combination of Versamune® HPV and KEYTRUDA® in Subjects with Recurrent or Metastatic HPV16-positive HNSCC KEYTRUDA®(pembrolizumab) FDA-Approved Standard of Care Partner StudyDesign Open-label, non-randomized, adaptive design study N=54 (ICI Naive) N=21 (ICI Resistant) Enrollment complete Key Entry Criteria for ICI Naïve Subjects Recurrent or metastatic HNSCC ≥18 years of age HPV16-Positive tumor Combined positive score (CPS) ≥1 Versamune® HPV1 Plus KEYTRUDA® 2 1 1 mL Subcutaneous injection at Cycles 1, 2, 3, 4 and 12) 2 200mg IV Q3W up to 35 Cycles (2 years) Study Treatment Primary: Best overall response (BOR) of confirmed complete response (CR) or confirmed partial response (PR) per RECIST 1.1 Key Secondary: Progression Free Survival (PFS) per RECIST 1.1 Overall Survival (OS) Safety and tolerability Endpoints Fast Track Designation

VERSATILE-002 First Line R/M HNSCCKey Demographics and Treatment Exposure Demographic ITT Population (N=55) Age, Median (Min, Max) 64.0 (46, 83) Sex, n (%) Male Female 51 (92.7) 4 (7.3) Race, n (%) American Indian or Alaska Native Asian Black or African American Pacific Islander White Other 0 1 (1.8) 1 (1.8) 0 52 (94.5) 1 (1.8) ECOG, n (%) 0 1 32 (58.2) 23 (41.8) CPS, n (%)* <1 1–19 ≥20 0 33 (60.0) 22 (40.0) Treatment Exposure(ITT Population) Median number of PDS0101 doses: 4 (range 1–5) 76.4% received ≥4 doses38.2% received 5 doses (5th dose is 6 months after dose 4) Median number of KEYTRUDA® doses: 8 (range 1–35) 43.6% received ≥10 doses Data on File. 02/15/24 Data Cut

Summary of VERSATILE-002 Results First Line Recurrent/Metastatic HNSCC VERSATILE-002 (Versamune® HPV + KEYTRUDA®) KEYNOTE-048 (KEYTRUDA®) CPS≥1 CPS≥20 CPS≥1 CPS≥20 Confirmed BOR (%) 34 48 19 23 Median PFS (months) 6.3 14.1 3.2 3.4 Median Overall Survival (months)* (Future Pivotal Trial Endpoint) 30.0 30.0 12.3 14.9 Confirmed Best Overall Response and Disease Control Rate Based on Investigator Assessment Per RECIST v1.1 by PD-L1 Expression Level, mITT Population Progression-Free Survival (PFS) Based on Investigator Assessment Per RECIST v1.1 by PD-L1 Expression Level, mITT Population No controlled or comparative studies have been conducted between checkpoint inhibitors and Versamune® HPV * FDA-recommended clinical endpoint Burtness B. et al. Lancet. 2019;394:1915-28. Data on File. 02/15/24 Data Cut

Median Overall Survival of 30 Months in mITT and ITT Populations Kaplan-Meier Estimates of OS in Recurrent/Metastatic HNSCC Data on File. 02/15/24 Data Cut Patients without a progression event or lost to follow up (N=2) at data cut off date – censor date is last date of tumor assessment

Versamune® HPV and KEYTRUDA® Combination Demonstrates Promising Survival In First Line R/M HNSCC * No controlled or comparative studies have been conducted between checkpoint inhibitors and PDS0101Data on File. 02/15/24 Data CutBurtness B et al., Lancet. 2019; 394:1915-1928 OS Rate (%) VERSATILE-002 VERSATILE-002 KEYNOTE-048(CPS≥1) KEYNOTE-048(CPS≥1) 12-month OS Rate Median Overall Survival (mOS) Keytruda® Chemotherapy + Keytruda® Versamune® HPV + Keytruda® Months

Durable Responses Reported with 75.5% of Patients with CPS ≥1 Having CR, PR or SD According to RECIST 1.1 Spider Plot Showing Disease State with Time in Recurrent/Metastatic HNSCC Data on File. 02/15/24 Data Cut

Disease Stabilization or Tumor Reduction Reported in 87% (46/53) of First Line Recurrent/Metastatic HNSCC Patients * Modified Intent-to-Treat: All ITT subjects who had at least 1 imaging assessment Best Percentage Change from Baseline in Target Lesions (mITT population*) Data on File. 02/15/24 Data Cut

Versamune® HPV and KEYTRUDA® Combination Well Tolerated in First Line R/M with No Grade 5 TRAE* Injection Site Related TRAEs n (%) Injection site pain 37 (59.7) Injection site swelling 19 (30.6) Injection site erythema 13 (21.0) Injection site warmth 11 (17.7) Injection site discoloration 9 (14.5) Injection site reaction 9 (14.5) Injection site inflammation 8 (12.9) Injection site pruritus 8 (12.9) Injection site rash 4 (6.5) All Other TRAEs n (%) Fatigue 23 (37.1) Headache 12 (19.4) Pruritis 9 (14.5) Diarrhea 7 (11.3) Rash 6 (9.7) Pain 5 (8.1) Alanine aminotransferase increased 4 (6.5) Aspartate aminotransferase increased 4 (6.5) Arthralgia 4 (6.5) Cough 4 (6.5) Malaise 4 (6.5) * TRAE = Treatment Related Adverse Event Data on File. 02/15/24 Data Cut TRAEs by Grade n (%) Any Combination TRAE 55 (88.7) Grade 1 29 (46.8) Grade 2 18 (29.0) Grade 3 7 (11.3) Grade 4 1 (1.6) Grade 5 0 Grade 3 Combination-TRAE were: Fatigue (2), Rash, Alanine aminotransferase increased, Blood alkaline phosphatase increased, Lymphocyte count decreased, Autoimmune colitis, Colitis, Headache, Acute kidney injury, Hyponatremia, Hyperglycemia, Grade 4 Combination-TRAE: encephalitis

VERSATILE-002 Conclusions VERSATILE-002 has successfully met its primary end point of 14 or more confirmed objective responses by RECIST v1.1 in ICI naïve patients with CPS ≥1 BOR by Investigator Assessment: 34% (CPS ≥1) and 48% (CPS ≥20) Versamune® HPV may significantly impact survival in first line treatment of recurrent and/or metastatic HPV16 positive head and neck cancer The median OS of 30 months and 12-month OS rate of 80% both exceed the best publicly reported survival results to date with both investigational and approved products in patients with CPS ≥1 The combination appears to be well tolerated Immunological and clinical data suggests that Versamune® HPV induces the right type and quantity of potent tumor targeting T cells that promote patient survival Data on File. 02/15/24 Data Cut

Synergistic Effect With SoC Modalities Across a Spectrum of Solid Tumors PDS01ADC and Versamune® Have Broad Therapeutic Potential PDS01ADC VERSAMUNE® Designed to deliver and sustain IL-12 in tumor Fused conjugate limits systemic presence and toxicity of IL-12 and also prevents free IL-12 Activates/expands T cells in tumor & limits T cell exhaustion Changes tumor to become more permissive to T cell attack Designed to train T cells to recognize the cancer Activates the right type of multifunctional CD8 killer T cells Promotes a long-lasting memory T cell response Promotes the right quantity and potency of T cells

Mechanism Attacks the Tumor from Both the Inside (TME) and Outside Potential first tumor-targeting immuno-cytokine antibody drug conjugate PDS01ADC + Versamune® + ICI: Unique Combined Mechanism Necrotic Core PDS01ADC binds to necrotic DNA Versamune® Activated Targeting CD8+ Killer T-Cell Oxygenated Area Inside PDS01ADC Infiltrates TME; Weakens Tumor’s Protection from Immune System Stimulates T Cells in TME to Promote Expansion + Prolonged, Effective Killing Outside Versamune® Induces Right Type & Quantity of Potent Killer T Cells that Target and Infiltrate Tumor Immune Checkpoint Inhibitor Restores Pre-existing T Cell Responses

Triple Combination Investigator-Initiated Trial: Phase 2 Clinical Trial Objective: To Assess the Triple Combination of Versamune® HPV plus PDS01ADC plus the Bi-functional Immune Checkpoint Inhibitor Bintrafusp alfa in Subjects with Recurrent or Metastatic HPV-positive Cancer IIT Partner StudyDesign Open-label, non-randomized, adaptive design study N=8 (up to 20 ICI Naïve allowed) N=29 (ICI Resistant) Key Entry Criteria for ICI Naïve Subjects Recurrent or metastatic HPV-positive cancer ≥18 years of age HPV-Positive tumor Anal Cervical Oropharyngeal Vaginal/vulvar Versamune® HPV1 Plus PDS01ADC2 Plus Bintrafusp alfa 3 1 1 mL Subcutaneous injection every 4 weeks for 6 doses followed by 2 doses at 12-week intervals 216.8mcg/kg Subcutaneous injection every 4 weeks, or 8mcg/kg every 2 weeks for up to one year 3 1200mg IV every 2 weeks up to one year Study Treatment Primary: Best overall response (BOR) of confirmed complete response (CR) or partial response (PR) per RECIST 1.1 in ICI naive Key Secondary: Overall Survival (OS) Safety and tolerability Endpoints Exploratory: Best overall response (BOR) of confirmed complete response (CR) or partial response (PR) per iRECIST 1.1 in ICI naïve and ICI resistant patients

Triple Combination Key Demographics and Treatment Exposure National Cancer Institute. (2023). Combination Immunotherapy in Subjects With Advanced HPV Associated Malignancies. [Data set] Demographic ITT Population (N=50) Age, Median (Min, Max) 56.0 (28, 80) Sex, n (%) Male Female 26 (52%) 24 (48%) Tumor Type, n (%) Anal Cervical Head and Neck Vaginal/Vulvar 10 (20%) 14 (28%) 23 (46%) 3 (6%) Prior Treatments, n (%) Chemotherapy Radiotherapy Immune Checkpoint Inhibitors 50 (100%) 45 (90%) 36 (72%) HPV Status, n (%) HPV+ HPV16+ Other HPV+ HPV-/Unknown Status 48 (96%) 37 (74%) 11 (22%) 2 (4%)

First Line Recurrent/Metastatic HPV16+ HNSCC: Versamune® HPV and PDS01ADC Promoted Strong Survival Benefit References: Burtness B. et al. Lancet. 2019;394:1915-28. Licitra L. et al. 2024 Multidisciplinary Head and Neck Cancers Symposium. February 29-March 2, 2024. PDS Biotech Data on File. National Cancer Institute. (2023). Combination Immunotherapy in Subjects With Advanced HPV Associated Malignancies. [Data set] Marabelle A et al. Lancet. 2022;7(5):446-454. Shapira-Frommer R et al. Gynecol Oncol. 2022;166(2):212-218. Chung HC et al. J Clin Oncol. 2019;37(17):1470-1478. https://ascopost.com/issues/march-25-2024/lenvatinib-plus-pembrolizumab-fails-to-improve-overall-survival-in-advanced-head-and-neck-cancer/ *Pembrolizumab reported median overall survival range in anal, cervical & vulvar cancers = 6-12 Months **Includes anal, cervical, HNSCC, vulvar cancers No controlled head-to-head trials have been performed between pembrolizumab and the Versamune® HPV combinations Survival of Patients with Recurrent/Metastatic HPV16+ Cancers HNSCC HNSCC HNSCC 12.3* Months 17.9* 30.0 42.3**

First Line Recurrent/Metastatic HPV16+ Cancer: Versamune® HPV and PDS01ADC Promoted Objective Responses References: PDS Biotech Data on File. National Cancer Institute. (2023). Combination Immunotherapy in Subjects With Advanced HPV Associated Malignancies. [Data set], KEYNOTE-158, Efficacy and safety of pembrolizumab on cervical cancer: A systematic review and single-arm meta-analysis Front. Oncol. 12:910486. doi: 10.3389/fonc.2022.910486, Dhawan, N.; Afzal, M.Z.Amin, M. Immunotherapy in Anal Cancer. Curr. Oncol. 2023, 30,4538–4550. https://doi.org/10.3390/curroncol30050343, https://doi.org/10.1016/S0140-6736(19)32591-7, https://ascopost.com/issues/march-25-2024/lenvatinib-plus-pembrolizumab-fails-to-improve-overall-survival-in-advanced-head-and-neck-cancer/ 34% (18/53) 75%** (6/8) No controlled head-to-head trials have been performed between KEYTRUDA® and the Versamune® HPV combinations Best Objective Response (BOR) 11-25%* *Pembrolizumab reported ORR range in anal, cervical, HNSCC & vulvar cancers = 11-25% **Includes anal, cervical, HNSCC, vulvar cancers; BOR assessment using iRECIST HNSCC

Phase 2 Triple Combination Results Indicate Favorable Tolerability 48% Had Grade 3 TRAEs, 4% Grade 4 Preferred Term n (%) Myocarditis 1 (2) Anemia 15 (30) HLH* 1 (2) Flu-like Symptoms 1 (2) Lymphopenia 3 (6) CPK Elevation 1 (2) Preferred Term n (%) Leukopenia 1 (2) Neutropenia 1 (2)** Hematuria 5 (10) GI Bleeding 2 (4) AST/ALT Elevation 4 (8)*** Mucositis 1 (2) Grade 3/4 Adverse Events (AE) Grade 3/4 Adverse Events (cont.) *HLH, hemophagocytic lymphohistiocytosis **Grade 4 TRAE ***1 patient had Grade 4 TRAE Safety Population: All enrolled subjects who received at least 1 dose of any drug. National Cancer Institute. (2023). Combination Immunotherapy in Subjects With Advanced HPV Associated Malignancies. [Data set]

Triple Combination Conclusions Triple Combination has successfully met its primary endpoint of at least a 60% confirmed objective response rate by RECIST v1.1 BOR = 63% (RECIST v1.1) BOR = 75% (iRECIST) Versamune® HPV + PDS01ADC + ICI may significantly impact survival in first line and second line treatment of recurrent and/or metastatic HPV16 positive cancer Median OS of 42 months in first line exceeds the best publicly reported results to date Median OS of 19-20 months in second line exceeds the best publicly reported results to date Triple Combination appears to be well tolerated Immunological and clinical data suggests that PDS01ADC may be effective in targeting the tumor to overcome immune suppression National Cancer Institute. (2023). Combination Immunotherapy in Subjects With Advanced HPV Associated Malignancies. [Data set]

Compelling Survival Data Supports Triple Combination Pivotal Study Supported by strong results in difficult-to-treat resistant patients with Triple Study VERSATILE-002 (NCT04260126) HPV16+ HNSCC Versamune® HPV + pembrolizumab N=53 mOS = 30 months NCI Triple Study* (NCT04287868) Advanced HPV16+ Cancers Versamune® HPV + PDS01ADC + ICI N=8 mOS = 42 months FIRST LINE R/M SECOND LINE R/M NCI Triple Study** (NCT04287868) Advanced HPV16+ Versamune® HPV + PDS01ADC + ICI N=29 mOS = 19-20 months Versamune® HPV + PDS01ADC + pembrolizumab Primary Endpoint mOS FIRST LINE R/M HNSCC PIVOTAL STUDY *Published Results with SOC pembrolizumab for Recurrent/Metastatic HPV+ Cancers (Anal, Cervical, HNSCC, Vulvar): mOS Range =6-12 Mos; ORR Range=11-14%; **Published results in ICI resistant patients with bifunctional ICI: mOS=3.4 months, ORR=10% Data on File. 02/15/24 Data Cut. National Cancer Institute. (2023). Combination Immunotherapy in Subjects With Advanced HPV Associated Malignancies. [Data set]

More Than 430 Patients Treated with PDS01ADC and/or Versamune® HPV Lead Program Supported and Validated by Robust Clinical Data PDS01ADC 300+ Patients Treated to Date HNSCC Patient Exposure Across Product Portfolio PDS01ADC + Versamune® HPV + Bintrafusp alfa (triple) and Versamune® HPV + pembrolizumab (double) administered to 110+ head & neck cancer patients to date Acceptable tolerability and safety profile to date at 12.0 and 16.8 μg/kg every 2 or 4 weeks Versamune® well-tolerated to date at 3.0 and 10.0 mg per dose every 3 weeks Versamune® HPV 170+ Patients Treated to Date

In Interviews, Oncologists Preferred use of Triple Combination in First Line Recurrent/ Metastatic HNSCC ICI: Immune Checkpoint Inhibitor Source: Triangle Insights Group Interviews with N=20 medical oncologists, conducted March 2024 On a scale of 1-7, the triple combination was rated 6.3 by oncologists for use in first line R/M HNSCC Not at All Favorable Very Favorable Preference as 1L Treatment: It would allow patients to bypass chemo New Standard of Care: Oncologists were confident that it would likely become new standard of care given the strong responses versus existing treatments “This is the way to go; a chemo-free way to treat patients. I think they will like it and the response is great.” – Medical Oncologist Perceived Benefits Perceived Concerns “No new concerns…the efficacy is so compelling that I would put up with this degree of toxicity; it is no problem” – Medical Oncologist Limited Concerns in 1L Use: Patients typically tolerate treatment better in earlier lines, oncologists were more optimistic about the triple therapy in the first line An improved safety profile may further raise the overall favorability of the product

Study Design – First Line Recurrent/Metastatic (VERSATILE-003 Plus) Dose Optimization 1:1 randomization Evaluate activity, safety, tolerability Randomized controlled trial 1:1:1 randomization OS primary endpoint Interim Analysis Versamune® HPV + PDS01ADC + pembrolizumab ~40 subjects ~350 subjects PDS01ADC dose selection Versamune® HPV + pembrolizumab Pembrolizumab FDA-aligned VERSATILE-003 protocol design Added triple combo arm to VERSATILE-003 Median Overall Survival (OS) endpoint and Study Size Designed for Potential Success in both Treatment Arms* 16.8 mcg/kg 12 mcg/kg FDA-aligned VERSATILE-003 protocol design *FDA meeting anticipated July 2024

Increasing Incidence Driven Largely by HPV16+ References: https://www.cdc.gov/cancer/hpv/basic_info/hpv_oropharyngeal.htm. Accessed January 30, 2024. Lechner M. et al. Nature. 2022 HNSCC: Devastating Cancers with High Prevalence and Mortality Oral and PharyngealCancers (~40% of HNSCC) Paranasalsinuses Nasopharynx Oropharynx Hypopharynx Larynx Pharynx Tongue Salivaryglands OralCavity NasalCavity Genotype of HPV-Positive Oral and Pharyngeal Cancer

Epidemiology-Based Estimate of Addressable Population: HNSCC Company market research HPV16-positive HNSCC Presents Significant Initial Market Opportunity No approved HPV-specific cancer therapy Significant unmet need Est. HPV16Locally Advanced,Unresectable andMetastatic HNSCC ~13,600 ~18,200 ~22,000 ~53,305 Est. U.S. HNSCC Est. U.S. HPV Positive HNSCC Est. HPV16 Genotype ~$2-3B Market Opportunity in US1

Candidate/ Study Indication PC P1 P2 P3 Partner PDS01ADC + Versamune® PDS01ADC + Versamune® HPV + ICI Recurrent or metastatic HPV16-positive HNSCC PDS01ADC + Versamune® MUC1 + ICI (Phase 1/2 anticipated 2024) Recurrent or metastatic colorectal cancer Versamune® Versamune® HPV + ICI (KEYTRUDA®) Recurrent or metastatic HPV16-positive HNSCC Versamune® Versamune® HPV + Chemo (IMMUNOCERV) 1st-line treatment of locally advanced(IB3-IVA) cervical cancer Versamune® Versamune® HPV +/- pembrolizumab Neo-adjuvant treatment of locally advanced HPV-positive oropharyngeal cancer (OPSCC) Pipeline Continues to Validate Platforms, Drive Future Opportunities Initiate pivotal study in HNSCC: PDS01ADC + Versamune® HPV + pembrolizumab Triple Combination – 2024 Update on regulatory confirmation of potentially registrational study - Q3-2024 Upcoming Milestones (2024) File IND for Versamune® MUC1 Triple Combination Phase 1/2 study in r/m colorectal cancer – Q4-2024 Provide clinical update on IMMUNOCERV trial – Q4-2024

Record of Execution in Development, Commercialization of Leading Pharmaceutical Products Veteran New Leadership to Execute Strategy Senior executive experience with management of strategy and execution at large pharma and biotechs Notable drug development: Abelcet® (Liposome Company/ Elan) PEG-Intron® (Schering-Plough/ Merck) Frank Bedu-Addo, PhD Chief Executive Officer 20 years of financial leadership rolesin healthcare Former Chief Financial Officer of publicly traded healthcare andbiotech companies Lars Boesgaard Chief Financial Officer US board-certified medicaloncologist and hematologist 30+ years of experience in the pharmaceutical industry Kirk Shepard, M.D. Chief Medical Officer Co-founder 35 years of drug development experience In-depth experience with biotechdrug discovery, productdevelopment and manufacturing Gregory Conn, PhD Chief Scientific Officer Stephan Toutain Chief Operating Officer 30 years of experience in the life sciences industry from drug development, general management, operations, commercial development, market access and sales

Thank You NASDAQ: PDSB