Active, not recruitingNCT04675294Updated Aug 1, 2025

Evorpacept (ALX148) in Combination With Pembrolizumab in Patients With Advanced Head and Neck Squamous Cell Carcinoma (ASPEN-03)

A Phase 2 interventional study of evorpacept and pembrolizumab in Head and Neck Cancer and Head and Neck Squamous Cell Carcinoma, sponsored by ALX Oncology Inc.. Active, not recruiting at 53 sites in 9 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-08-01.

Sponsored by ALX Oncology Inc. · Phase 2, Interventional, and Treatment

Phase: Phase 2
Study type: Interventional
Enrollment: 189
Allocation: Randomized
Ages: 18 Years and older
Sex: All

Study summary

A Phase 2 Study of evorpacept (ALX148) in Combination With pembrolizumab in Patients With Advanced Head and Neck Squamous Cell Carcinoma.

Read the detailed description

This is a open-label, randomized phase 2 multi-center study of the anti-tumor efficacy of evorpacept (ALX148) + pembrolizumab and of pembrolizumab alone in patients with metastatic or unresectable, recurrent HNSCC that is PD-L1 positive (CPS ≥1 by an FDA-approved test) and who have not yet been treated for their advanced disease. The study comprises an initial safety lead-in cohort followed by a randomized portion.

Conditions studied

Head and Neck Cancer
Head and Neck Squamous Cell Carcinoma

Browse trials for

Keywords

ALX148
CD47
SIRPα
HNSCC
pembrolizumab
evorpacept

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: No

Inclusion criteria

Patients with metastatic or unresectable, recurrent head and neck squamous cell carcinoma (HNSCC) that is PD-L1 positive (CPS > 1) and who have not received prior systemic therapy for their advanced disease.
Adequate bone marrow function.
Adequate renal and liver function.
Adequate ECOG performance status.

Exclusion criteria

Exclusion Criteria:

Patients with known symptomatic CNS metastases or leptomeningeal disease requiring steroids.
History of (non-infectious) pneumonitis that required steroids or has current pneumonitis.
Prior treatment with any anti-CD47 or anti-SIRPα agent.
Prior treatment with anti-PD-1 or PD-L1.

Study design

Phase: Phase 2
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel assignment
Masking: None (open label)
Enrollment: 189 participants (actual)

Study arms

Experimental
evorpacept (ALX148) + pembrolizumab
evorpacept (ALX148) 45 mg/kg IV and pembrolizumab 200 mg IV given every 3 weeks.
Drug: evorpacept · Drug: pembrolizumab
Active comparator
pembrolizumab
pembrolizumab 200 mg IV given every 3 weeks.
Drug: pembrolizumab

Interventions

Drugevorpacept
IV Q3W
Also known as: ALX148
Drugpembrolizumab
IV Q3W
Also known as: KEYTRUDA®

What researchers measure

Primary outcomes

Objective response rate per RECIST 1.1
Time frame: Last randomized patient reaching at least 24 weeks of follow-up

Secondary outcomes

Duration of response
Time frame: Up to 36 months
Progression-free survival
Time frame: Up to 36 months
Overall survival
Time frame: Up to 36 months
Adverse events
Time frame: Up to 36 months

Study locations

53 sites

Hoag Hospital
Irvine, California 92618, United States
University of California San Diego
La Jolla, California 92037, United States
H. Lee Moffitt Cancer Center
Tampa, Florida 33612, United States
Northwest Georgia Oncology Centers
Marietta, Georgia 30060, United States
Rush University Medical Center
Chicago, Illinois 60612, United States
Blessing Cancer Center
Quincy, Illinois 62301, United States
University of Maryland Medical System
Baltimore, Maryland 21201, United States
Massachusetts General Hospital
Boston, Massachusetts 02114, United States
Rutgers Cancer Institute of New Jersey
Newark, New Jersey 07103, United States
Memorial Sloan-Kettering Cancer Center
Long Island City, New York 11101, United States
The Ohio State University
Columbus, Ohio 43210, United States
Oregon Health & Science University
Portland, Oregon 97239, United States
Vanderbilt - Ingram Cancer Center
Nashville, Tennessee 37232, United States
Houston Methodist Cancer Center
Houston, Texas 77030, United States
St. Vincent's
Sydney, New South Wales 2146, Australia
Royal Brisbane and Womens Hospital
Brisbane, Queensland 4029, Australia
Peter MacCallum Cancer Centre
Melbourne, Victoria 3051, Australia
Sir Charles Gairdner Hospital
Perth, Western Australia 6009, Australia
Ashford Cancer Centre Research
Windsor Gardens, 5087, Australia
Cliniques Universitaires Saint-Luc
Brussels, 1200, Belgium
AZ Groeninge
Kortrijk, 8500, Belgium
UZ Leuven
Leuven, B - 3000, Belgium
Hamilton Health Sciences - Juravinski Cancer Centre
Hamilton, Ontario L9G2X1, Canada
LHSC - Victoria Hospital
London, Ontario N6A5W9, Canada
Ottawa Hospital Cancer Centre
Ottawa, Ontario K1H 8L6, Canada
Princess Margaret Cancer Centre
Toronto, Ontario, Canada
VUMC Goederenontvangst
Amsterdam, 1081, Netherlands
Universitair Medisch Centrum Groningen
Groningen, 9713, Netherlands
National University Cancer Institute
Singapore, 119074, Singapore
National Cancer Centre Singapore
Singapore, 169610, Singapore
Chungbuk National University Hospital
Cheongju-si, 28644, South Korea
Yeungnam University Medical Center
Daegu, 42415, South Korea
Chungnam National University Hospital
Daejeon, 35015, South Korea
CHA University of Bundang
Gyeonggi-do, 13496, South Korea
Gachon University - Gil Medical Center
Incheon, 21565, South Korea
Seoul National University Bundang Hospital
Seongnam, 13620, South Korea
Korea University Medical Center (KUMC) - Korea University Anam Hospital
Seoul, 02841, South Korea
Seoul National University Hospital
Seoul, 03080, South Korea
The Catholic University of Korea - Eunpyeong St. Mary's Hospital
Seoul, 03312, South Korea
Samsung Medical Center
Seoul, 06351, South Korea
SNU Boramae Medical Center
Seoul, 07061, South Korea
Severance Hospital Yonsei University
Seoul, 3722, South Korea
Catholic University of Korea, St. Vincent's Hospital Suwon
Suwon, 16247, South Korea
Yonsei University - Wonju Severance Christian Hospital
Wŏnju, 26426, South Korea
Hospital Universitari Dexeus
Barcelona, Barcelona 08028, Spain
Institud Catala d´Oncologia
Barcelona, 08908, Spain
Hospital Universitario La Paz
Madrid, 28046, Spain
HM Sanchinarro
Madrid, 28050, Spain
Hospital Severo Ochoa
Madrid, 28911, Spain
Hospital Regional Universitario de Malaga
Málaga, 29010, Spain
Hospital Universitario de Navarra
Pamplona, 31008, Spain
Royal Marsden NHS Foundation Trust
London, SW3 6JJ, United Kingdom
Royal Marsden NHS Foundation Trust
Sutton, SM2 5PT, United Kingdom

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

Registry details

Key details

Study ID: NCT04675294
Lead sponsor: ALX Oncology Inc.
Collaborators: Merck Sharp & Dohme LLC
Responsible party: Sponsor
First posted: Dec 19, 2020
Start date: Apr 2, 2021
Primary completion: Mar 3, 2025
Completion: Jun 30, 2026 (estimated)
Last update: Aug 1, 2025

Oversight

Data monitoring committee: No
FDA-regulated drug: Yes
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is active, not recruiting, as verified in Jul 2025. You cannot join it, but the record below documents what was studied.

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