IMFINZI® (durvalumab) regimen reduced the risk of disease recurrence or death by 32% in high-risk non-muscle-invasive bladder cancer in the POTOMAC Phase III trial

Adding one year of IMFINZI treatment to Bacillus Calmette-Guérin (BCG) induction and maintenance therapy delivered an early and sustained disease-free survival benefit vs. BCG alone

WILMINGTON, Del.–(BUSINESS WIRE)–Positive results from the POTOMAC Phase III trial showed adding one year of treatment with AstraZeneca’s IMFINZI^® (durvalumab) to BCG induction and maintenance therapy demonstrated a statistically significant and clinically meaningful improvement in disease-free survival (DFS) for patients with BCG-naïve, high-risk non-muscle-invasive bladder cancer (NMIBC) compared to BCG treatment alone.

The results of this final analysis will be presented today during a late-breaking Proffered Paper session at the European Society for Medical Oncology (ESMO) Congress 2025 in Berlin, Germany (abstract #LBA108) and simultaneously published in The Lancet.

With a median follow-up of more than five years (60.7 months), the IMFINZI regimen showed a 32% reduction in the risk of high-risk disease recurrence or death versus the comparator arm (based on a DFS hazard ratio [HR] of 0.68; 95% confidence interval [CI] 0.50-0.93; P=0.0154). Estimated median DFS was not yet reached for either arm. An estimated 87% of patients treated with the IMFINZI regimen remained alive and disease-free at two years compared to 82% in the comparator arm.

The trial was not statistically powered to formally test overall survival (OS); however, after a median follow-up of more than five years (65.6 months, 14% maturity), a descriptive analysis showed an OS HR of 0.80 (95% CI 0.53-1.20), demonstrating that there was no detriment to OS.

Maria De Santis, MD, Head of the Interdisciplinary Uro-Oncology Section at Charité – Universitätsmedizin Berlin, Germany, and a principal investigator in the POTOMAC trial, said: “While patients with early-stage bladder cancer are treated with the goal of cure, early recurrence is common among those with high-risk non-muscle-invasive bladder cancer. This can lead to repeated surgical procedures and more intensive treatment, including removing a patient’s bladder which deeply affects their quality of life. The results of POTOMAC showed that adding one year of durvalumab to BCG bladder instillation treatment reduced the risk of recurrence by 32 per cent, allowing more patients to remain disease-free and alive at two years.”

Susan Galbraith, Executive Vice President, Oncology Haematology R&D, AstraZeneca, said: “The early and sustained disease-free survival benefit observed in the POTOMAC trial demonstrates IMFINZI has the potential to change the course of high-risk non-muscle-invasive bladder cancer by extending the time patients live without high-risk disease recurrence or progression. These results build on IMFINZI’s practice-changing impact in muscle-invasive bladder cancer and further validate our strategy to bring novel therapies into earlier-stage disease where they can have the greatest impact on patients’ lives.”

Summary of results: POTOMAC

	IMFINZI-based regimen (n=339)	BCG induction and maintenance (n=340)
DFS
Number of patients with event (%)	67 (20)	98 (29)
Median DFS (95% CI) (in months)i,ii,iii	NRiv (NR-NR)	NR (74.0-NR)
HR (95% CI)	0.68 (0.50-0.93)
Stratified log-rank p-valuev	0.0154
DFS rate at 12 months (%)	91.7	86.8
DFS rate at 24 months (%)	86.5	81.6
DFS rate at 36 months (%)	81.8	77.4
OSvi
Number of deaths (%)	41 (12)	52 (15)
HR (95% CI)	0.80 (0.53-1.20)
Median OS (95% CI) (in months)i	NR (NR-NR)	NR (NR-NR)
i. DFS cut-off date was April 3, 2025 i. Median follow-up duration for DFS at data cutoff: 60.7 months (interquartile range, 51.5-66.5) ii. Calculated by Kaplan-Meier method iii. Not reached iv. For statistical significance, a 2-sided p-value of less than 0.0317, as determined by the Haybittle-Peto spending function, was required v. Descriptive analysis, ITT; 14% maturity

The safety and tolerability of IMFINZI plus BCG induction and maintenance therapy was consistent with the known safety profiles of the individual medicines, with no new safety concerns identified. Grade 3 and 4 adverse events due to any cause occurred in 34% of patients treated with the IMFINZI regimen and 17% of patients in the comparator arm. The addition of IMFINZI did not compromise patients’ ability to complete BCG induction and maintenance therapy and had no major impact on patient-reported quality of life, supporting the benefit-risk profile of this combination.

IMFINZI is approved in the US, the European Union (EU), Japan and other countries for patients with muscle-invasive bladder cancer (MIBC) based on results from the NIAGARA Phase III trial, and continues to be investigated across early and late-stage bladder cancer in various treatment combinations, including in patients with MIBC who are ineligible or refuse to take cisplatin (VOLGA) and in locally advanced or metastatic disease (NILE).

IMPORTANT SAFETY INFORMATION

There are no contraindications for IMFINZI^® (durvalumab) or IMJUDO^® (tremelimumab-actl).

Severe and Fatal Immune-Mediated Adverse Reactions

Important immune-mediated adverse reactions listed under Warnings and Precautions may not include all possible severe and fatal immune-mediated reactions. Immune-mediated adverse reactions, which may be severe or fatal, can occur in any organ system or tissue. Immune-mediated adverse reactions can occur at any time after starting treatment or after discontinuation. Monitor patients closely for symptoms and signs that may be clinical manifestations of underlying immune-mediated adverse reactions. Evaluate clinical chemistries including liver enzymes, creatinine, adrenocorticotropic hormone (ACTH) level, and thyroid function at baseline and before each dose. In cases of suspected immune-mediated adverse reactions, initiate appropriate workup to exclude alternative etiologies, including infection. Institute medical management promptly, including specialty consultation as appropriate. Withhold or permanently discontinue IMFINZI and IMJUDO depending on severity. See USPI Dosing and Administration for specific details. In general, if IMFINZI and IMJUDO requires interruption or discontinuation, administer systemic corticosteroid therapy (1 mg to 2 mg/kg/day prednisone or equivalent) until improvement to Grade 1 or less. Upon improvement to Grade 1 or less, initiate corticosteroid taper and continue to taper over at least 1 month. Consider administration of other systemic immunosuppressants in patients whose immune-mediated adverse reactions are not controlled with corticosteroid therapy.

Immune-Mediated Pneumonitis

IMFINZI and IMJUDO can cause immune-mediated pneumonitis, which may be fatal. The incidence of pneumonitis is higher in patients who have received prior thoracic radiation.

• IMFINZI as a Single Agent
  • In patients who did not receive recent prior radiation, the incidence of immune-mediated pneumonitis was 2.4% (34/1414), including fatal (<0.1%), and Grade 3-4 (0.4%) adverse reactions.
  • In patients who received recent prior radiation, the incidence of pneumonitis (including radiation pneumonitis) in patients with unresectable Stage III NSCLC following definitive chemoradiation within 42 days prior to initiation of IMFINZI in PACIFIC was 18.3% (87/475) in patients receiving IMFINZI and 12.8% (30/234) in patients receiving placebo. Of the patients who received IMFINZI (475), 1.1% were fatal and 2.7% were Grade 3 adverse reactions.
  • The incidence of pneumonitis (including radiation pneumonitis) in patients with LS-SCLC following chemoradiation within 42 days prior to initiation of IMFINZI in ADRIATIC was 14% (37/262) in patients receiving IMFINZI and 6% (16/265) in patients receiving placebo. Of the patients who received IMFINZI (262), 0.4% had a fatal adverse reaction and 2.7% had Grade 3 adverse reactions.
  • The frequency and severity of immune-mediated pneumonitis in patients who did not receive definitive chemoradiation prior to IMFINZI were similar in patients who received IMFINZI as a single agent or with ES-SCLC or BTC when given in combination with chemotherapy.
• IMFINZI with IMJUDO
  • Immune‑mediated pneumonitis occurred in 1.3% (5/388) of patients receiving IMFINZI and IMJUDO, including fatal (0.3%) and Grade 3 (0.2%) adverse reactions.
• IMFINZI with IMJUDO and Platinum-Based Chemotherapy
  • Immune-mediated pneumonitis occurred in 3.5% (21/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including fatal (0.5%), and Grade 3 (1%) adverse reactions.

Immune-Mediated Colitis

IMFINZI with IMJUDO and platinum-based chemotherapy can cause immune-mediated colitis, which may be fatal.

IMFINZI and IMJUDO can cause immune-mediated colitis that is frequently associated with diarrhea. Cytomegalovirus (CMV) infection/reactivation has been reported in patients with corticosteroid-refractory immune-mediated colitis. In cases of corticosteroid-refractory colitis, consider repeating infectious workup to exclude alternative etiologies.

• IMFINZI as a Single Agent
  • Immune-mediated colitis occurred in 2% (37/1889) of patients receiving IMFINZI, including Grade 4 (<0.1%) and Grade 3 (0.4%) adverse reactions.
• IMFINZI with IMJUDO
  • Immune‑mediated colitis or diarrhea occurred in 6% (23/388) of patients receiving IMFINZI and IMJUDO, including Grade 3 (3.6%) adverse reactions. Intestinal perforation has been observed in other studies of IMFINZI and IMJUDO.
• IMFINZI with IMJUDO and Platinum-Based Chemotherapy
  • Immune-mediated colitis occurred in 6.5% (39/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy including fatal (0.2%) and Grade 3 (2.5%) adverse reactions. Intestinal perforation and large intestine perforation were reported in 0.1% of patients.

Immune-Mediated Hepatitis

IMFINZI and IMJUDO can cause immune-mediated hepatitis, which may be fatal.

• IMFINZI as a Single Agent
  • Immune-mediated hepatitis occurred in 2.8% (52/1889) of patients receiving IMFINZI, including fatal (0.2%), Grade 4 (0.3%) and Grade 3 (1.4%) adverse reactions.
• IMFINZI with IMJUDO
  • Immune‑mediated hepatitis occurred in 7.5% (29/388) of patients receiving IMFINZI and IMJUDO, including fatal (0.8%), Grade 4 (0.3%) and Grade 3 (4.1%) adverse reactions.
• IMFINZI with IMJUDO and Platinum-Based Chemotherapy
  • Immune-mediated hepatitis occurred in 3.9% (23/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including fatal (0.3%), Grade 4 (0.5%), and Grade 3 (2%) adverse reactions.

Immune-Mediated Endocrinopathies

• Adrenal Insufficiency: IMFINZI and IMJUDO can cause primary or secondary adrenal insufficiency. For Grade 2 or higher adrenal insufficiency, initiate symptomatic treatment, including hormone replacement as clinically indicated.
  • IMFINZI as a Single Agent
    • Immune-mediated adrenal insufficiency occurred in 0.5% (9/1889) of patients receiving IMFINZI, including Grade 3 (<0.1%) adverse reactions.
  • IMFINZI with IMJUDO
    • Immune-mediated adrenal insufficiency occurred in 1.5% (6/388) of patients receiving IMFINZI and IMJUDO, including Grade 3 (0.3%) adverse reactions.
  • IMFINZI with IMJUDO and Platinum-Based Chemotherapy
    • Immune-mediated adrenal insufficiency occurred in 2.2% (13/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including Grade 3 (0.8%) adverse reactions.
• Hypophysitis: IMFINZI and IMJUDO can cause immune-mediated hypophysitis. Hypophysitis can present with acute symptoms associated with mass effect such as headache, photophobia, or visual field cuts. Hypophysitis can cause hypopituitarism. Initiate symptomatic treatment including hormone replacement as clinically indicated.
  • IMFINZI as a Single Agent
    • Grade 3 hypophysitis/hypopituitarism occurred in <0.1% (1/1889) of patients who received IMFINZI.
  • IMFINZI with IMJUDO
    • Immune-mediated hypophysitis/hypopituitarism occurred in 1% (4/388) of patients receiving IMFINZI and IMJUDO.
  • IMFINZI with IMJUDO and Platinum-Based Chemotherapy
    • Immune-mediated hypophysitis occurred in 1.3% (8/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including Grade 3 (0.5%) adverse reactions.
• Thyroid Disorders (Thyroiditis, Hyperthyroidism, and Hypothyroidism): IMFINZI and IMJUDO can cause immune-mediated thyroid disorders. Thyroiditis can present with or without endocrinopathy. Hypothyroidism can follow hyperthyroidism. Initiate hormone replacement therapy for hypothyroidism or institute medical management of hyperthyroidism as clinically indicated.
  • IMFINZI as a Single Agent
    • Immune-mediated thyroiditis occurred in 0.5% (9/1889) of patients receiving IMFINZI, including Grade 3 (<0.1%) adverse reactions.
    • Immune-mediated hyperthyroidism occurred in 2.1% (39/1889) of patients receiving IMFINZI.
    • Immune-mediated hypothyroidism occurred in 8.3% (156/1889) of patients receiving IMFINZI, including Grade 3 (<0.1%) adverse reactions.
  • IMFINZI with IMJUDO
    • Immune-mediated thyroiditis occurred in 1.5% (6/388) of patients receiving IMFINZI and IMJUDO.
    • Immune-mediated hyperthyroidism occurred in 4.6% (18/388) of patients receiving IMFINZI and IMJUDO, including Grade 3 (0.3%) adverse reactions.
    • Immune-mediated hypothyroidism occurred in 11% (42/388) of patients receiving IMFINZI and IMJUDO.
  • IMFINZI with IMJUDO and Platinum-Based Chemotherapy
    • Immune-mediated thyroiditis occurred in 1.2% (7/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy.
    • Immune-mediated hyperthyroidism occurred in 5% (30/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including Grade 3 (0.2%) adverse reactions.
    • Immune-mediated hypothyroidism occurred in 8.6% (51/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including Grade 3 (0.5%) adverse reactions.
  • IMFINZI with Carboplatin and Paclitaxel
    • Immune-mediated hypothyroidism occurred in 14% (34/235) of patients receiving IMFINZI in combination with carboplatin and paclitaxel.
• Type 1 Diabetes Mellitus, which can present with diabetic ketoacidosis: Monitor patients for hyperglycemia or other signs and symptoms of diabetes. Initiate treatment with insulin as clinically indicated.
  • IMFINZI as a Single Agent
    • Grade 3 immune-mediated Type 1 diabetes mellitus occurred in <0.1% (1/1889) of patients receiving IMFINZI.
  • IMFINZI with IMJUDO
    • Two patients (0.5%, 2/388) had events of hyperglycemia requiring insulin therapy that had not resolved at last follow-up.
  • IMFINZI with IMJUDO and Platinum-Based Chemotherapy
    • Immune-mediated Type 1 diabetes mellitus occurred in 0.5% (3/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy including Grade 3 (0.3%) adverse reactions.

Immune-Mediated Nephritis with Renal Dysfunction

IMFINZI and IMJUDO can cause immune-mediated nephritis.

• IMFINZI as a Single Agent
  • Immune-mediated nephritis occurred in 0.5% (10/1889) of patients receiving IMFINZI, including Grade 3 (<0.1%) adverse reactions.
• IMFINZI with IMJUDO
  • Immune-mediated nephritis occurred in 1% (4/388) of patients receiving IMFINZI and IMJUDO, including Grade 3 (0.5%) adverse reactions.
• IMFINZI with IMJUDO and Platinum-Based Chemotherapy
  • Immune-mediated nephritis occurred in 0.7% (4/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including Grade 3 (0.2%) adverse reactions.

Immune-Mediated Dermatology Reactions

IMFINZI and IMJUDO can cause immune-mediated rash or dermatitis. Exfoliative dermatitis, including Stevens-Johnson Syndrome (SJS), drug rash with eosinophilia and systemic symptoms (DRESS), and toxic epidermal necrolysis (TEN), has occurred with PD-1/L-1 and CTLA-4 blocking antibodies. Topical emollients and/or topical corticosteroids may be adequate to treat mild to moderate non-exfoliative rashes.

• IMFINZI as a Single Agent
  • Immune-mediated rash or dermatitis occurred in 1.8% (34/1889) of patients receiving IMFINZI, including Grade 3 (0.4%) adverse reactions.
• IMFINZI with IMJUDO
  • Immune-mediated rash or dermatitis occurred in 4.9% (19/388) of patients receiving IMFINZI and IMJUDO, including Grade 4 (0.3%) and Grade 3 (1.5%) adverse reactions.
• IMFINZI with IMJUDO and Platinum-Based Chemotherapy
  • Immune-mediated rash or dermatitis occurred in 7.2% (43/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including Grade 3 (0.3%) adverse reactions.

Immune-Mediated Pancreatitis

IMFINZI in combination with IMJUDO can cause immune-mediated pancreatitis. Immune-mediated pancreatitis occurred in 2.3% (9/388) of patients receiving IMFINZI and IMJUDO, including Grade 4 (0.3%) and Grade 3 (1.5%) adverse reactions.

Other Immune-Mediated Adverse Reactions

The following clinically significant, immune-mediated adverse reactions occurred at an incidence of less than 1% each in patients who received IMFINZI and IMJUDO or were reported with the use of other immune-checkpoint inhibitors.

• Cardiac/vascular: Myocarditis, pericarditis, vasculitis.
• Nervous system: Meningitis, encephalitis, myelitis and demyelination, myasthenic syndrome/myasthenia gravis (including exacerbation), Guillain-Barré syndrome, nerve paresis, autoimmune neuropathy.
• Ocular: Uveitis, iritis, and other ocular inflammatory toxicities can occur. Some cases can be associated with retinal detachment. Various grades of visual impairment to include blindness can occur. If uveitis occurs in combination with other immune-mediated adverse reactions, consider a Vogt-Koyanagi-Harada-like syndrome, as this may require treatment with systemic steroids to reduce the risk of permanent vision loss.
• Gastrointestinal: Pancreatitis including increases in serum amylase and lipase levels, gastritis, duodenitis.
• Musculoskeletal and connective tissue disorders: Myositis/polymyositis, rhabdomyolysis and associated sequelae including renal failure, arthritis, polymyalgia rheumatic.
• Endocrine: Hypoparathyroidism.
• Other (hematologic/immune): Hemolytic anemia, aplastic anemia, hemophagocytic lymphohistiocytosis, systemic inflammatory response syndrome, histiocytic necrotizing lymphadenitis (Kikuchi lymphadenitis), sarcoidosis, immune thrombocytopenia, solid organ transplant rejection, other transplant (including corneal graft) rejection.

Infusion-Related Reactions

IMFINZI and IMJUDO can cause severe or life-threatening infusion-related reactions. Monitor for signs and symptoms of infusion-related reactions. Interrupt, slow the rate of, or permanently discontinue IMFINZI and IMJUDO based on the severity. See USPI Dosing and Administration for specific details. For Grade 1 or 2 infusion-related reactions, consider using pre-medications with subsequent doses.

• IMFINZI as a Single Agent
  • Infusion-related reactions occurred in 2.2% (42/1889) of patients receiving IMFINZI, including Grade 3 (0.3%) adverse reactions.
• IMFINZI with IMJUDO
  • Infusion-related reactions occurred in 2.6% (10/388) of patients receiving IMFINZI and IMJUDO.
• IMFINZI with IMJUDO and Platinum-Based Chemotherapy
  • Infusion-related reactions occurred in 2.9% (17/596) of patients receiving IMFINZI in combination with IMJUDO and platinum-based chemotherapy, including Grade 3 (0.3%) adverse reactions.

Complications of Allogeneic HSCT after IMFINZI

Fatal and other serious complications can occur in patients who receive allogeneic hematopoietic stem cell transplantation (HSCT) before or after being treated with a PD-1/L-1 blocking antibody. Transplant-related complications include hyperacute graft-versus-host disease (GVHD), acute GVHD, chronic GVHD, hepatic veno-occlusive disease (VOD) after reduced intensity conditioning, and steroid-requiring febrile syndrome (without an identified infectious cause). These complications may occur despite intervening therapy between PD-1/L-1 blockade and allogeneic HSCT. Follow patients closely for evidence of transplant-related complications and intervene promptly. Consider the benefit versus risks of treatment with a PD-1/L-1 blocking antibody prior to or after an allogeneic HSCT.

Embryo-Fetal Toxicity

Based on their mechanism of action and data from animal studies, IMFINZI and IMJUDO can cause fetal harm when administered to a pregnant woman. Advise pregnant women of the potential risk to a fetus. In females of reproductive potential, verify pregnancy status prior to initiating IMFINZI and IMJUDO and advise them to use effective contraception during treatment with IMFINZI and IMJUDO and for 3 months after the last dose of IMFINZI and IMJUDO.

Lactation

There is no information regarding the presence of IMFINZI and IMJUDO in human milk; however, because of the potential for serious adverse reactions in breastfed infants from IMFINZI and IMJUDO, advise women not to breastfeed during treatment and for 3 months after the last dose.

Adverse Reactions

Unresectable Stage III NSCLC

• In patients with Stage III NSCLC in the PACIFIC study receiving IMFINZI (n=475), the most common adverse reactions (≥20%) were cough (40%), fatigue (34%), pneumonitis or radiation pneumonitis (34%), upper respiratory tract infections (26%), dyspnea (25%), and rash (23%). The most common Grade 3 or 4 adverse reactions (≥3%) were pneumonia (7%) and pneumonitis/radiation pneumonitis (3.4%).
• In patients with Stage III NSCLC in the PACIFIC study receiving IMFINZI (n=475), discontinuation due to adverse reactions occurred in 15% of patients in the IMFINZI arm. Serious adverse reactions occurred in 29% of patients receiving IMFINZI. The most frequent serious adverse reactions (≥2%) were pneumonitis or radiation pneumonitis (7%) and pneumonia (6%). Fatal pneumonitis or radiation pneumonitis and fatal pneumonia occurred in <2% of patients and were similar across arms.

Resectable NSCLC

• In patients with resectable NSCLC in the AEGEAN study, the most common adverse reactions (occurring in ≥20% of patients) were anemia, nausea, constipation, fatigue, musculoskeletal pain, and rash.
• In patients with resectable NSCLC in the neoadjuvant phase of the AEGEAN study receiving IMFINZI in combination with platinum-containing chemotherapy (n=401), permanent discontinuation of IMFINZI due to an adverse reaction occurred in 6.7% of patients. Serious adverse reactions occurred in 21% of patients. The most frequent (≥1%) serious adverse reactions were pneumonia (2.7%), anemia (1.5%), myelosuppression (1.5%), vomiting (1.2%), neutropenia (1%), and acute kidney injury (1%). Fatal adverse reactions occurred in 2% of patients, including death due to COVID-19 pneumonia (0.5%), sepsis (0.5%), myocarditis (0.2%), decreased appetite (0.2%), hemoptysis (0.2%), and death not otherwise specified (0.2%). Of the 401 IMFINZI treated patients who received neoadjuvant treatment and 398 placebo-treated patients who received neoadjuvant treatment, 1.7% (n=7) and 1% (n=4), respectively, did not receive surgery due to adverse reactions.
• In patients with resectable NSCLC in the adjuvant phase of the AEGEAN study receiving IMFINZI as a single agent (n=265), permanent discontinuation of IMFINZI due to an adverse reaction occurred in 8% of patients.

Contacts

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US Media Mailbox: usmediateam@astrazeneca.com

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