A Phase 2 Study of Vapendavir in Asthmatic Adults With Symptomatic Human Rhinovirus Infection

This is a multicenter trial to be conducted at approximately 60 sites among 6−8 northern
hemisphere countries in North America and Central Europe. Sufficient patients will be
randomized in order to recruit 150 subjects who are laboratory confirmed for human rhinovirus
(HRV) infection. Depending on HRV PCR positivity rates, it is expected that randomization of
250-480 subjects will be required to achieve this number of subjects with HRV infection.

Appropriate asthma subjects will be screened up to 180 days prior to presentation at the
study site with symptoms of presumed HRV infection for potential study inclusion on Study Day
1. The study drug treatment period has a duration of 7 days, beginning on Study Day 1.
Follow-up study visits to the clinic occur on Study Days 3, 5, 7, 14, 21, and 28 with a
telephonic final safety follow-up visit conducted on Study Day 35. Thus, depending on the
duration of the screening period, a subject's duration of participation can be estimated to
last from approximately 37 days up to 215 days.

Inclusion Criteria:

1. Moderate and severe male and female asthma subjects aged 18 to 75 years, (inclusive)

2. Established clinical history of Asthma for at least 1 year, and a history within the
last 14 months (prior to screening) of asthma exacerbation due to presumed viral
respiratory infections, which required asthma rescue medication treatment.

3. The asthma subjects will be currently taking at least medium-dose or high-dose ICS
defined as fluticasone at a dosage of at least >264 µg daily and may be taking other
asthma medication preparations. The asthma subjects' medication regimen must be stable
for at least 4 weeks before screening.

4. Subjects will have at screening or within the last year, documented variable airway
obstruction as indicated by an increase in FEV1 (>12%) to short acting bronchodilator,
or positive methacholine challenge, or positive histamine challenge (PC20 <8 mg/mL).

5. Upon presentation to the clinic with cold symptoms, subjects will be required to be
randomized and treated within 48 hours of symptom onset and will be qualified for
presumptive rhinovirus infection by:

1. clinical exam and the presence of each of the following Day 1 WURSS-21 symptoms
at a severity of 2 or greater: runny nose, sore throat, scratchy throat.

2. subjects must also have a minimum total symptom score on the Day 1 WURSS-21 of 20
points.

3. subjects will be further qualified as presumptively infected with HRV via
exclusion of subjects having significant fever and exclusion of subjects testing
positive for influenza via Rapid Antigen Test.

Exclusion Criteria:

1. Subjects presenting to the clinic with a current severe asthma exacerbation will be
excluded from randomization, as well as any subject with an additional underlying
respiratory medical condition other than asthma such as COPD, cystic fibrosis, or
chronic sinusitis, or any other uncontrolled clinically significant disease which
would interfere with the assessment outcomes or subject safety.

2. Female subjects must not be pregnant or breastfeeding. Females of childbearing
potential must be willing to utilize a double barrier method of contraception, as
defined in this protocol, regardless of any hormonal contraception they may be
concomitantly receiving.

3. Male subjects must agree to use a method of birth control defined in this protocol.

4. The use of medications known to moderately or severely inhibit or induce cytochrome
(CYP) 3A4 and 2C19 enzymes, or those known to be sensitive substrates (with a narrow
therapeutic range) of these CYPs are restricted.