Trial Outcomes & Findings for Additional Recombinant COVID-19 Humoral and Cell-Mediated Immunogenicity in Immunosuppressed Populations (NCT NCT06027229)

NCT ID: NCT06027229

Last Updated: 2025-10-20

Results Overview

Antibody concentrations 1 month after the recombinant vaccine booster (V2) in patients with IBD and solid organ transplant recipients compared to their baseline visit (V1).

• Recruitment status: COMPLETED
• Study phase: PHASE2
• Target enrollment: 21 participants
• Primary outcome timeframe: baseline and 1 month
• Results posted on: 2025-10-20

Participant Flow

21 participants were assessed for eligibility, 1 patient was withdrawn due to inadvertent administration of an messenger ribonucleic acid (mRNA) vaccine.

Participant milestones

Measure	Immunosuppressed Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have Irritable Bowel Disease (IBD) and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Overall Study STARTED	20
Overall Study Follow-Up	20
Overall Study Analysis Population	20
Overall Study COMPLETED	20
Overall Study NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Only participants with IBD are counted in this measure.

Baseline characteristics by cohort

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Age, Continuous	47.6 years STANDARD_DEVIATION 14.9 • n=20 Participants
Sex: Female, Male Female	9 Participants n=20 Participants
Sex: Female, Male Male	11 Participants n=20 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=20 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	20 Participants n=20 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=20 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=20 Participants
Race (NIH/OMB) Asian	0 Participants n=20 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=20 Participants
Race (NIH/OMB) Black or African American	0 Participants n=20 Participants
Race (NIH/OMB) White	20 Participants n=20 Participants
Race (NIH/OMB) More than one race	0 Participants n=20 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=20 Participants
Region of Enrollment United States	20 participants n=20 Participants
Body Mass Index (BMI)	79.59 kilograms per meter squared STANDARD_DEVIATION 10.2 • n=20 Participants
Smoking Status Never	14 Participants n=20 Participants
Smoking Status Former	6 Participants n=20 Participants
Smoking Status Current	0 Participants n=20 Participants
Type of Immunosuppression IBD	17 Participants n=20 Participants
Type of Immunosuppression Solid Organ Transplantation	3 Participants n=20 Participants
Type of IBD Proctitis	1 Participants n=17 Participants • Only participants with IBD are counted in this measure.
Type of IBD Proctosigmoiditis	1 Participants n=17 Participants • Only participants with IBD are counted in this measure.
Type of IBD Left Sided Disease	1 Participants n=17 Participants • Only participants with IBD are counted in this measure.
Type of IBD Pancolitis	2 Participants n=17 Participants • Only participants with IBD are counted in this measure.
Previous Surgical Resection	6 Participants n=20 Participants
Length of IBD	16 years STANDARD_DEVIATION 12.2 • n=17 Participants • Only participants with IBD are counted in this measure.
Current IBD Medications Azathioprine	1 Participants n=17 Participants • 17 participants have IBD
Current IBD Medications Metho	2 Participants n=17 Participants • 17 participants have IBD
Current IBD Medications Remicade	4 Participants n=17 Participants • 17 participants have IBD
Current IBD Medications Humira	4 Participants n=17 Participants • 17 participants have IBD
Current IBD Medications Entyvio	5 Participants n=17 Participants • 17 participants have IBD
Current IBD Medications Stelara	2 Participants n=17 Participants • 17 participants have IBD
Current IBD Medications Xeljanz	1 Participants n=17 Participants • 17 participants have IBD
Current IBD Medications Skyrizi	1 Participants n=17 Participants • 17 participants have IBD
Type of Transplant Liver	1 Participants n=3 Participants • 3 participants had solid organ transplant
Type of Transplant Lung	2 Participants n=3 Participants • 3 participants had solid organ transplant
Current Transplantation Medications Prednisone	2 Participants n=3 Participants • 3 participants had solid organ transplant
Current Transplantation Medications Azathioprine	1 Participants n=3 Participants • 3 participants had solid organ transplant
Current Transplantation Medications Tacrolimus	3 Participants n=3 Participants • 3 participants had solid organ transplant
Current Transplantation Medications Mycophenolate	2 Participants n=3 Participants • 3 participants had solid organ transplant
History of COVID-19 infection Never	9 Participants n=20 Participants
History of COVID-19 infection Once	8 Participants n=20 Participants
History of COVID-19 infection Twice	2 Participants n=20 Participants
History of COVID-19 infection Thrice	1 Participants n=20 Participants
Number of COVID-19 Vaccines Received	4.7 vaccinations n=20 Participants

PRIMARY outcome

Timeframe: baseline and 1 month

Antibody concentrations 1 month after the recombinant vaccine booster (V2) in patients with IBD and solid organ transplant recipients compared to their baseline visit (V1).

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Change in Antibody Concentration From Baseline (Visit 1) at 1 Month (Visit 2) baseline	22968.5 Endotoxin Units per milliliter (EU/mL) Interval 12081.4 to 43666.4
Change in Antibody Concentration From Baseline (Visit 1) at 1 Month (Visit 2) 1 month	66639 Endotoxin Units per milliliter (EU/mL) Interval 37915.5 to 117124.0

SECONDARY outcome

Timeframe: baseline, 1 month, 6 months

Seropositive will be defined by positive anti-receptor binding domain (RBD) IgG antibodies specific to SARS-CoV-2 performed by Labcorp.

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Seropositivity Rates baseline	20 Participants
Seropositivity Rates 1 month	20 Participants
Seropositivity Rates 6 months	20 Participants

SECONDARY outcome

Timeframe: baseline, 1 month, 6 months

Percentages (and 2-sided 95% Confidence Intervals) of participants who were seronegative at baseline and became seropositive after immunization will be evaluated in each group. For initially seropositive subjects at V1, antibody concentration at post-vaccination (V2) ≥ 4 fold the pre-vaccination antibody concentration.

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Percent of Participants Seronegative at Baseline and Subsequently Seropositive baseline	0 Participants
Percent of Participants Seronegative at Baseline and Subsequently Seropositive 1 month	0 Participants
Percent of Participants Seronegative at Baseline and Subsequently Seropositive 6 months	0 Participants

SECONDARY outcome

Timeframe: baseline and 1 month

An interferon gamma response will be considered any measurable response, reported is change in cells per million from baseline to 1 month.

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Change in Interferon Gamma Responses at 1 Month Compared to Baseline	28 cells per million Standard Deviation 101

SECONDARY outcome

Timeframe: 1 month, 6 months

An interferon gamma response will be considered any measurable response, reported is change in cells per million from 1 month to 6 months.

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Change in Interferon Gamma Responses at 6 Months Compared to 1 Month	-0.625 cells per million Standard Deviation 164

SECONDARY outcome

Timeframe: up to 7 days on study

The number of participants reporting each solicited local AE and each solicited systemic AE within seven days (Days 1-7) after the booster dose and overall will be summarized.

• Solicited local AEs included injection site pain, redness, and swelling.
• Solicited systemic AEs included fatigue, myalgia, arthralgia, headache, shivering/chills, fever, and gastrointestinal symptoms (nausea, vomiting, diarrhea, and abdominal pain).

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Solicited Adverse Events (AEs)	12 Participants

SECONDARY outcome

Timeframe: up to 30 days on study

The number of participants reporting unsolicited AEs within 30 days (Days 1-30) after the booster dose and overall will be summarized for both the study groups.

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Unsolicited Adverse Events	1 Participants

SECONDARY outcome

Timeframe: up to 6 months

The number of participants reporting pIMDs from the booster dose to the study end will be summarized.

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Potential Immune-Mediated Diseases (pIMDs)	0 Participants

SECONDARY outcome

Timeframe: up to 6 months

The number of participants reporting SAEs and fatal SAEs from the booster dose administration to the study end will be summarized for both the study groups.

Outcome measures

Measure	Immunosuppressed Participants n=20 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Serious Adverse Events (SAEs)	0 Participants

SECONDARY outcome

Timeframe: up to 6 months

Population: 17 participants had IBD

Disease activity will be assessed by monitoring disease activity using the Short Crohn's Activity Index (SCAI)18 for patients with Crohn's disease or the Simple Clinical Colitis Activity Index (SCCAI) questionnaire for patients with Ulcerative colitis at the baseline visit (V1), V2, and V3 visits. The incidence of IBD flares will be evaluated in all patients receiving recombinant boosters. This will be quantified by patients who were in clinical remission who develop a disease flare after receiving a recombinant COVID-19 booster.

Outcome measures

Measure	Immunosuppressed Participants n=17 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Number of Participants Reporting Disease Flares of IBD	0 Participants

SECONDARY outcome

Timeframe: up to 6 months

Population: 3 participants had solid organ transplants

Participants will be asked if they have been diagnosed with acute rejection after their baseline visit (V1). Episodes of acute rejection will be collected by searching electronic medical records and asking patients at each clinic visit (V2 and V3). Acute rejection will be defined as a notation of a new episode of acute rejection (cellular or antibody-mediated), a steroid bolus and taper in the absence of another indication, or administration of a T or B cell depleting agent or immune globulin. This will be quantified by patients who were who developing acute rejection of their transplant after receiving a recombinant COVID-19 booster.

Outcome measures

Measure	Immunosuppressed Participants n=3 Participants Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Number of Participants Reporting Acute Rejection of Their Transplant	0 Participants

Adverse Events

Immunosuppressed Participants

Serious events: 0 serious events

Other events: 12 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Measure	Immunosuppressed Participants n=20 participants at risk Male and females aged 18 to 85 who are solid organ transplant recipients or have IBD and receive the study intervention. NVX-CoV2372: Novavax COVID-19 Vaccine Booster for Omicron XBB.1.5
Injury, poisoning and procedural complications Injection Site Pain	40.0% 8/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
General disorders Headache	50.0% 10/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
General disorders Paresthesia	5.0% 1/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
General disorders Gastrointestinal Symptoms	20.0% 4/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
General disorders Shivering or Chills	10.0% 2/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
General disorders Arthralgia	45.0% 9/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
General disorders Myalgia	25.0% 5/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
General disorders Fatigue	40.0% 8/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
Injury, poisoning and procedural complications Injection Site Swelling	5.0% 1/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
Gastrointestinal disorders Hematemesis	5.0% 1/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
Gastrointestinal disorders Hematochezia	5.0% 1/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.
Renal and urinary disorders Hematuria	5.0% 1/20 • up to 180 days post-booster Participants were instructed to contact the study team if they experienced fever, chills, or rash. 7 days after each vaccination, participants were contacted to assess for solicited adverse events and to document any unsolicited adverse events. Local reactions (e.g., injection site pain, redness, swelling) and systemic symptoms (e.g., fever, headache, fatigue, myalgia) were recorded for 7 days following each dose, while unsolicited adverse events were monitored for 30 days.

Additional Information

Dr. Freddy Caldera, DO, PhD, MS

UW School of Medicine and Public Health

Phone: (608) 263-1995

Email: fcaldera@medicine.wisc.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place