Vet Examining Dog

Canine Oncology Treatment Data

Intratumoral (IT) administration of MIE-201 has demonstrated durable and systemic antitumor activity as a single agent and in combination treatment regimens in studies of canine patients with several different cancers.

Antitumor Activity Observed in Naturally Occurring Canine Cancers

>25 dogs treated to date

Single Agent     

  • Mammary cancer (MC) (unpublished)

  • Inflammatory mammary cancer (IMC)

Combination Treatment

  • Melanoma with radiation

  • IMC with chemotherapy

  • Carcinoma with radiation + hyperthermia

Overall Observations

• Single agent anti-tumor activity

• Combination treatment activity

• Increased recruitment of immune cells into tumors

• Systemic anti-tumor responses (abscopal effect observed)

• Positive safety profile

Canine Data: Broad and Consistent Immune Activation and Antitumor Effects

MIE-201 in Combination with Radiation Demonstrates Durable Complete Tumor Responses in Canine Patients with Oral Melanoma

Study Design

n = 3,  radiation + MIE-201

n = 2,  radiation only

 = 6 Gy radiation

 = Intratumoral MIE-201

Week 1

Week 2

Follow up

Results

  • All MIE-201 treated canines achieved complete tumor responses with no recurrence

  • 2 canines receiving radiation alone were euthanized due to tumor progression

  • Significant increase in immune cell infiltration of tumors receiving MIE-201

Hoopes P.J., Wagner R.J.,Duval K., Kang K., Gladstone D.J., Moodie K.L., Crary-Burney M., Ariaspulido H., Veliz F.A., Steinmetz N.F., Fiering S.N. (2018) Treatment of canine oral melanoma with nanotechnology-based immunotherapy and radiation. Mol Pharm., 15, 3717-3722. PMID: 29613803, PMCID: PMC6296751.

 Tumor Regressions Observed in Canine Inflammatory Mammary Cancer (IMC) Patients Treated with Two-Week Neoadjuvant in situ MIE-201

Study Design

A:  n = 5,  Standard of Care (SOC) only, (control)

B:  n = 5,  2-week single-agent MIE-201 followed by combination with SOC

A:   Control animals

B:   MIE-201 treated animals

100

P8

P9

P10

P6

0

200

300

% Tumor volume change relative to day 0

% Tumor volume change relative to day 0

-100

-75

0

20

40

60

80

D0

Dx

Dy

-50

-25

-5

0

20

P1

P2

P3

P4

P5

Days after treatment initiation

Days after treatment initiation

Tumor regressions observed in canine IMC patients treated with neoadjuvant in situ MIE-201,  (A, B).

Tumor volume as percentage of volume relative to D0. (A) %tumor volume change in control canine IMC patients treated with medical therapy from D0, but no MIE-201 therapy. Tumor volume changes in P7 during follow-up were not available. (B) % tumor volume change in MIE-201-treated IMC patients. Dx refers to measurements done at D7 (P1, P2, P3, P4) and D9 (P5). Dy refers to measurements at D14 (P2, P3); D15 (P4), D17 (P5) and D19 (P1). Black arrows indicate MIE-201 immunotherapy for all dogs; blue, for P1, P2 and P4.

Kaplan Meier Overall Survival, Neoadjuvant MIE-201 in IMC 

Overall  Survival

0.5

1.0

 Standard of Care (SOC) only

 2-week MIE-201, then + SOC

p = 0.033

0.0

0

50

100

150

200

Days after treatment initiation

Mean Survival

 67 days (SOC control)

 134 days (MIE-201 + SOC)

Summary

  • All MIE-201-treated patients demonstrated reductions in tumor size after roughly two weeks (monotherapy)

  • In two patients, the reduction in tumor size supported a decision to surgically remove the tumor, which is very rare for IMC treatment given IMC’s highly aggressive nature

  • All control patients showed tumor growth during the course of the study 

  • Survival of the MIE-201-treated patients was significantly extended (p=0.033) as compared to control patients

  • Increased CD8+ T cells and ratio of CD8+ T cells vs Treg cells in MIE-201 treated patients

  • Increased neutrophil infiltration into tumors in MIE-201 treated patients

  • No toxicities or adverse events were observed using MIE-201 treatment

Daniel Alonso-Miguel, Guillermo Valdivia, Diego Guerrera, Maria Dolores Perez-Alenza, Stanislav Pantelyushin, Angela Alonso-Diez, Veronique Beiss, Steven Fiering, Nicole F Steinmetz, Maria Suarez-Redondo, Johannes Vom Berg, Laura Peña, Hugo Arias-Pulido (2022) Neoadjuvant in situ vaccination with cowpea mosaic virus as a novel therapy against canine inflammatory mammary cancer. Journal for ImmunoTherapy of Cancer 2022;10:e004044. doi:10.1136/jitc-2021-004044.

If you are a veterinarian interested in learning more about MIE-201 and our plans for its continued development for the treatment of canine cancers, please  contact us.