Treatment of Mild-moderate Clostridium Difficile Infection (CDI)
Treatment of Mild-moderate Clostridium Difficile Infection (CDI)
Patients diagnosed to have mild-moderate CDI will be randomized to receive IM-01 egg-derived
 anti-C. difficile polyclonal antibodies in increasing dosages, twice daily, for a total of 10
 - 14 days. Resolution of diarrhea and other symptoms and fecal test parameters will be used
 to assess clinical effectiveness of Immunotherapy with IM-01 antibodies. Patients will be
 followed for recurrence of CDI. Subjects who are assessed as non-respondents to IM-01 will be
 reassessed and treated with standard of care CDI antibiotics for 10 -14 days.
INTRODUCTION: BACKGROUND INFORMATION AND SCIENTIFIC RATIONALE The increased incidence of
 antibiotic resistant 'superbugs' has amplified the use of broad spectrum antibiotics
 worldwide. An unintended consequence of antimicrobial treatment is disruption of
 gastrointestinal microbiota, resulting in susceptibility to opportunistic pathogens, such as
 Clostridium difficile (C. difficile).

 C. difficile is a gram-positive, spore-forming, anaerobic bacterium that causes hospital and
 community-acquired enteric infections resulting in C. difficile-associated diarrhea, pseudo
 membranous colitis, colitis and death.

 Clostridium difficile infection (CDI) remains the predominant cause of health care
 -associated infectious diarrhea, centered mainly in hospitals but also in the community at a
 rate of ~100/100,000 population and affecting the elderly disproportionately. Antimicrobial
 damage to the intestinal microbiome combined with the acquisition of spores of C. difficile
 is the main cause of pathogenesis. CDI is endemic in hospitals, and although infection
 control measures have reduced nosocomial rates of CDI in Canada over the past 5 years,
 community cases now appear to be more apparent .Treatment of CDI utilizes alternate
 antimicrobials directed at the pathogen, mainly metronidazole, vancomycin, or fidaxomicin
 given for a recommended 10-14 days. While the majority respond to antibiotic treatment,
 subsequent recurrences of CDI are observed in 25-40% of patients. Recurrences of CDI are
 retreated with the same antibiotics and due to the non-selective spectrum of activity of
 metronidazole and vancomycin, recurrences are increasing in probabilities for subsequent
 recurrences. Fidaxomicin is relatively more selective and its use is associated with reduced
 recurrences, but the high cost of fidaxomicin has restricted the usage.

 C. difficile infection is a serious diarrheal illness associated with substantial morbidity
 and mortality and is responsible for hospital and community-acquired diarrhea, pseudo
 membranous colitis colitis and death..

 ImmuniMed Inc. has developed an oral Immunotherapy using egg-derived anti- C. difficile
 polyclonal antibodies (IM-01), that directly targets the virulence factors of C. difficile.
 IM-01 is produced from chicken eggs following the immunization of laying hens with C.
 difficile virulent antigens, C. difficile toxin A, toxin B, C. difficile whole cells and C.
 difficile spores. IM-01 is in the form of spray-dried whole egg powder (yolk plus egg white
 containing ovalbumin) and is very stable for functional activity. Upon reconstitution, IM-01
 is administered orally, which allows it to reach to the intestinal lumen, where C. difficile
 toxins exert their toxic effects. In addition, IM-01 antibodies bind to C. difficile toxins
 and spores and neutralize their biological activities in vitro.

 The use of polyclonal antibodies derived from chicken eggs (IgY) to confer passive immunity
 has gained attention as a novel strategy for oral immunotherapy as an alternative to
 antibiotics for treatment of intestinal pathogens which cause diarrhea in animals and humans
 including, enterotoxigenic E. coli, Salmonella spp, and both bovine and human rotaviruses.
 Compared with mammalian antibodies (IgG), chicken egg-derived antibodies (IgY) have high
 antigen-specificity and avidity, react more rapidly to the same antigens and differ from
 mammalian antibodies (IgG) in both structural and immunological properties.. Compared to IgG,
 IgY is more stable in gut at pH 3.5 -11 and better tolerates enzymatic degradation by trypsin
 and chymotrypsin; the stability of IgY against pepsin is pH-dependent.

 Immunimed has determined that IgY polyclonal antibodies-specific to E. coli in egg powder
 containing albumin, are functionally stable when stored at 2-8°C for over 10 years.

 This makes IM-01 antibodies attractive for oral immunotherapy since eggs are normal dietary
 components, with no known toxic side effects. The IM-01 antibodies are shown to bind with C.
 difficile toxins and spores as well as to neutralize their biological activities in vitro.

 Compared with active vaccination, passive immunotherapy using IM-01 egg-derived polyclonal
 anti-C. difficile antibodies has advantages including: (i) rapid and local onset of action,
 (ii) highly specific activity, (iii) applicability to a broader range of patients from
 children to adults including immunocompromised patients, (iv) strategically can be applied
 for a specific event when it occurs, in contrast to a vaccination model where large
 populations need to be treated in advance and sustain active antibodies for long-durations,
 and (v) is a normal part of human diet.

 In a published literature, hamsters treated orally with C. difficile anti-toxin A and
 anti-toxin B neutralizing egg-derived polyclonal antibodies were protected following C.
 difficile challenge. Also, hamsters treated with egg-derived antibodies did not develop
 relapsing disease months after the treatment with antibodies. .

 Furthermore, egg-derived polyclonal antibodies have several advantages over the monoclonal
 antibodies (MAbs), since MAbs are generally specific for single epitope, when polyclonal
 antibodies - a new class of biopharmaceuticals, that have higher affinities for multiple
 target antigens and can recognize multiple epitopes resulting in superior potency; since they
 can recognize multiple toxin epitopes as it is relevant to polymorphism of the toxin A and
 toxin B genes in C. difficile.

 A piglet study was performed to demonstrate the safety and therapeutic effect of egg-derived
 polyclonal antibodies -specific to E. coli K-88, in farm animals. It has been established
 that E. coli K88 that cause diarrhea in piglets by colonizing in the lower GI tract of
 piglets improve their growth performance following treatment with E. coli K-88-specific
 antibodies orally.Furthermore, the highest body weight gain was achieved in pigs which were
 fed with the highest dosage of E. coli K-88 antibodies (4kg/1000 kg of nursery diet) compared
 to the lowest antibody dosage (1kg /1000 kg of nursery diet).

 It was concluded that feeding of piglets with egg-derived polyclonal antibodies-specific to
 E. coli K-88 results in significantly improved growth performance in an antibody
 dose-dependent manner. The manufacturing process for egg-derived polyclonal antibodies
 targeted to enterotoxigenic E. coli has been approved and validated by the Canadian Center
 for Veterinary Biologics.

 In conclusion oral Immunotherapy using polyclonal antibodies is considered to have a high
 safety profile with a low likelihood of adverse effects. If proven to be effective as an
 anti-infective approach, antibiotic selection pressure could be reduced, a key strategy to
 limit antibiotic resistance in C. difficile infections.

 IM-01 is spray-dried egg powder product containing polyclonal antibodies -specific to C.
 difficile toxins A and toxin B, plus antibodies to C, difficile spores. A 20g/day dosage of
 IM-01 was selected based on a pre-clinical animal study data, using piglets to treat with C.
 difficile enteritis.disease with 0.6g of IM-01 orally daily for 4 days.

 Under compassionate grounds, patients with confirmed CDI clinical diagnosis with unformed
 diarrheal stools, abdominal cramps and a positive stool test for the presence of toxins
 and/or C. difficile in culture, 106 patients (ages: 11-93 years) were enrolled for the
 clinical study. All patients signed informed consent forms to participate in the study. The
 amount of IM-01 antibody powder product (10g or 20g) orally administered daily by each
 patient with 150 mL of milk and followed for up to 6-week period following IM-01
 immunotherapy. Seventy six patients received an oral dose of 20 g of IM-01 and 30 patients
 received 10 g of IM-01 powder daily for 10 consecutive days, as drinkable therapy with milk
 or chocolate milk. The primary endpoint of the study was to eradicate C. difficile in stool
 samples.

 Of the 106 patients treated with IM-01 therapy,101 patients showed significant improvement of
 clinical symptoms with negative stool test results for CDI.Five patients showed reduced
 clinical symptoms during IM-01 treatment period. No recurrence was observed with IM-01
 therapy during the follow up period. No safety concerns were reported.

 Standard of care (SOC) antibiotics for the treatment of CDI have observed responses to
 treatment i.e. resolution of diarrhea and ancillary symptoms/signs in 72-88% of subjects, and
 for those subjects who do achieve resolution of CDI, ~16-24% experience a recurrence of CDI
 within an 8 week follow up. Non-responders are treated with higher dosages of vancomycin. day
 interval. A post-treatment minimal follow up period of 30 days has been used in recent RCTs
 of antimicrobials. Other trials have used several time points i.e 8 weeks or 12 weeks post
 -treatment. Therefore, in absence of a standard of care control arm, the foregoing response
 rates for resolution of CDI symptoms (~80%), and a recurrence rate of 20% will be used for as
 a response template for this study. In the absence of randomization of subjects to an
 antibiotic treatment control group,
Inclusion Criteria:

 In order to be eligible to participate in this study, an individual must meet all of the
 following criteria:

 -  Provide signed and dated informed consent form

 -  Willing to comply with all study procedures and be available for the duration of the
 study

 -  Male or female, aged 18 to 89

 -  In good general health as evidenced by medical history or Diagnosed with specific
 condition/disease or Exhibits specific clinical signs or symptoms or physical/oral
 examination findings

 -  Participant has a diagnosis of CDI defined as (i) presence of diarrhea with 4 or more
 unformed stools within 24 hours and (ii) positive test for toxigenic C. difficile from
 stools collected within 7 days.

 -  Participants received < 24 h of SOC therapy for CDI.

 -  Participants presented with primary CDI episode or first recurrence of CDI

 -  Participants comply with the eligibility criteria and willing to participate in the
 study including the 8 week post treatment follow up period.

 -  White Blood Cell absolute neutrophil count <15 x 109/L,

 -  Women of reproductive potential must use highly effective contraception. For those
 with child bearing potential, the following methods of birth control are required from
 Visit 1 up to at least 30 days after study treatment discontinuation: 1). Diaphragm,
 female condom or cervical cap, partner's use of a condom, any of which must be used in
 combination with a spermicide; 2). Intra-uterine device; 3). Oral or injectable
 contraceptive agent, implant, or transdermal contraceptive hormone patches. If a
 hormonal contraceptive is used, it must have been taken for at least one month prior
 to enrolment/randomization; 4). Sterilization method (tubal ligation/occlusion, or
 partner's vasectomy); 5). True abstinence from intercourse with a male partner only
 when this is in line with the preferred lifestyle of the subject.

 -  Men of reproductive potential must use condoms-

 Exclusion Criteria:

 An individual who meets any of the following criteria will be excluded from participation
 in this study:

 -  known allergic reactions to chicken egg components.

 -  Female of child bearing potential and not receiving contraception; pregnant or
 lactating persons.

 -  severe CDI defined as >10 unformed bowel movements (UBMs)/24 h period, fever >38.5 o
 C, White Blood Cell count > 15 x 109/L, abdominal pain and tenderness on physical
 examination, toxic megacolon, ileus, nausea, vomiting.

 -  receipt of > 24 h of SOC treatment of CDI, or fecal microbial transplant (FMT) prior
 to enrollment.

 -  treatment with another investigational drug or other intervention within 30 days prior
 to enrollment including intravenous immunoglobulin (IVIG) or monoclonal intravenous
 (IV) antibody.

 -  received vaccine for C. difficile.

 -  concurrent use of probiotics of any type during treatment and follow up.

 -  unable to discontinue use of opiates for diarrhea control.

 -  co-infection with another gastrointestinal (GI) pathogen.

 -  presence of Inflammatory Bowel Disease (IBS), IBS with diarrhea (IBS-D), chronic
 diarrhea of unknown cause.

 -  any condition that hinders oral consumption. Exception: nasogastric tubes can be used
 to administer the product.

 -  death likely within study interval.

 -  any circumstance or medical condition under the Investigator's opinion that precludes
 participation.