Understanding the Spectrum of ENPP1 Deficiency and Acute ABCC6 Deficiency Through the Eyes of Patients and Parents; Burden of Illness Perspectives From Patients and Parents Who Speak English, French or German
Conditions: Generalized Arterial Calcification in Infancy, Autosomal Recessive Hypophosphatemic Rickets Type 2
Sponsor: Inozyme Pharma

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Name and Address of Sponsor/Company: 
Inozyme Pharma 
321 Summer St Floor 4 
Boston MA 02210 
Protocol Number: INZ701-004 
Protocol Version and Date: Version 1.0, April 6, 2020 
Amendment Number and Date, If Applicable: Not applicable 
Name of Investigational Product: 
Not applicable 
Title of Study:  
Understanding the Spectrum of ENPP1 Deficiency and Acute ABCC6 Deficiency Through 
the Eyes of Patients and Parents; Burden of Illness Perspectives from Patients and Parents 
who Speak English, French or German   
Phase of development:  
Not applicable 
Background:  
ENPP1 deficiency is a systemic and progressive disorder with high morbidity and mortality. 
Biallelic, loss of function mutations in the ENPP1 gene, which encodes the ENPP1 enzyme, 
cause ENPP1 deficiency. In rare cases, biallelic mutations in the ABCC6 gene which encodes 
the ABCC6 transporter cause a disorder resembling the acute infantile form of ENPP1 
deficiency. Both proteins produce extracellular pyrophosphate (PPi), a key regulator of 
mineralization, directly (ENNP1) or indirectly (ABCC6). The condition leads to pathological 
mineralization of arteries and arterial neo-intimal proliferation; calcification of joints and 
organs; organ dysfunction; hypophosphatemia rickets; short stature; developmental and 
cognitive delays; osteomalacia; pain and poor quality of life. 
ENPP1 deficiency and the acute form of ABCC6 deficiency present as a continuum of 
progressive signs and symptoms throughout life. ENPP1 deficiency and ABCC6 deficiency 
share an acute infantile phase characterized by ectopic calficication of the major arteries 
leading to high mortality from major cardiovascular events MI, CVA, AS, etc.). Pediatric 
subjects surviving this phase go on to develop morbid complications of disease, including 

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phosphate wasting and the development of rickets. Adults with ENPP1 deficiency experience 
organ and tissue calcification, physiological deterioration, and significant morbidity.  
Hypopyrophosphatemia (low pyrophosphate [PPi]) is pathognomonic of ENPP1 deficiency, 
and may explain the acute form of ABCC6 deficiency, throughout all of its phases. This key 
biochemical defect in patients drives the progression of all the known pathologic calcification 
disorders found in all stages of the disease. 
To date, we lack characterization of, the burden of, and the systemic progression of disease in 
ENPP1 deficiency and ABCC6 deficiency from a patient and/or parent perspective. This 
study aims to document this characterization, progression as well as the burden of disease. 
Note: Historically, alternate terminology was used that referred to ENPP1 deficient patients 
as having GACI Type 1 and ABCC6 deficient patients as having GACI Type 2. Additionally, 
many patients who survive GACI go on to develop ARHR2, which is usually associated with 
the ENPP1 gene. Because many patients impacted by ENPP1 or ABCC6 deficiency were 
diagnosed using these alternate terms, all patient-facing materials in the study utilize the 
terms GACI and ARHR2 as well as ENPP1 or ABCC6 deficiency. 
Objectives:  
• 
To improve the understanding of the characterization and burden of disease in 
ENPP1deficient, and acute ABCC6 deficient, patients who are still growing and 
those who are done growing  
• 
To collect information regarding disease burden, in the patient’s / families own 
terms 
• 
To build a foundation of evidence to contribute to the dossier, used for many 
purposes, including reimbursement and regulatory bodies. 
Study Design: 
This will be a comprehensive, cross-sectional study conducted in approximately 60 
individuals (or representative parents of patients) affected by ENPP1 deficiency and the acute 
form of ABCC6 deficiency. All study participants will complete the RSVP, PRO tools and 
upload a proof of disease form, followed by an interview conducted by a trained interviewer. 
It is estimated that each respondent will need up to 60 minutes for the entire process; 20 
minutes to complete the RSVP, PRO tools and to upload proof of diagnosis of ENPP1 
deficiency or the acute form of ABBC6 deficiency, and approximately 40 minutes to 
complete the interview and address any follow-up questions if needed.  
 

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Study Methods (see Appendix A) 
Roles 
The study will be sponsored by Inozyme. Study design and questions were developed 
with input from clinical experts, Inozyme’s Chief Medical Officer, Pedro Huertas, MD, 
PhD, and Christine O’Brien, Co-President of GACI Global (the disease patient support 
organization), Engage Health (a health research firm), and representatives of Inozyme. 
Engage Health will conduct interviews and perform statistical analysis. Central IRB 
approval will be obtained prior to the initiation of the study.  
 
Recruitment and Recruitment Materials (see Appendix B) 
Participants will be recruited in territories where individuals speak English, German or 
French (these are likely to be Germany, France, the UK, Canada, Australia and the U.S.) 
from various sources including GACI Global, social media, and from Engage Health’s 
proprietary EnCompass® database, in which patients have opted in to be notified of 
research opportunities. Sample recruitment materials (text only) including email 
outreaches and social media posts are provided in Appendix B of this document. A web 
page that describes the study can be found in Appendix C of this document. The 
researchers will seek to recruit 60 participants across four groups; person or parent/legal 
guardian affected by ENPP1 (GACI or ARHR2) or the acute form of ABCC6 deficiency 
as described below;  
• 
Acute infantile ENPP1 deficiency (note; due to the high infant mortality, this 
group is likely to include parents of affected children, both living and deceased) 
• 
Acute infantile ABCC6 deficiency (note; due to the high infant mortality, this 
group is likely to include parents of affected children, both living and deceased) 
• 
Progressive pediatric ENPP1 deficiency who are still growing (note; due to the 
age of those who are still growing, this group is likely to include parents of 
affected children) 
• 
Adult ENPP1 deficiency who are no longer growing (note: due to the age of 
those who are no longer growing, this group is likely to include both patients > 
age 18 years and parents of affected children who are < age 18 years or who are 
unable to answer for themselves) 
 
Consent and Assent (see Appendix D) 
Each interested individual will visit an on-line RSVP site and complete an online 
informed Consent form to participate in the study. If a person is under the age of 18 and 
would like to participate in the PRO portion of the study, they will be asked to fill out the 

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online Assent. If the individual has research-related questions about the study, the 
individual will be directed to Dr. Pedro Huertas at (978) 394-5700, who will answer the 
questions. A copy of the signed and dated informed consent/assent can be printed from 
the site by the participant. 
 
RSVP Survey and Interview Data (see Appendix E) 
After the consent/assent is signed, the individual will provide answers to demographic 
questions, including ethnicity, Personal Data (which will be used to schedule the 
telephone interview) including name, telephone number, email address, and address. 
Personal information is required for purposes of setting up the interview, conducting the 
interview and paying honoraria. The email address and telephone number may also be 
used for data clarification if necessary (see Quality Control). They will also provide age 
in months and years of the person impacted by ENPP1 or ABCC6 deficiency. Based on 
the age, they will see age-appropriate validated tools: Ages and Stages Questionnaire ™; 
PedsQL ™ or PROMIS ®; participants and caregivers for those over age three years will 
see the Brief Pain Inventory. These will be printed by the participant, filled out manually, 
and uploaded to the site.  
 
Each respondent will provide "proof of disease" (such as genetic diagnosis from a 
relevant testing laboratory, physician consult notes, school note describing 
accommodations and disease name, or medical record of diagnosis) by uploading it to the 
site, and will denote times that will work for them to participate in the telephone 
interview. If there is difficulty uploading the completed PRO forms or proof of disease, 
study participants will complete the RSVP, and the staff of Engage Health will contact 
them in order to assist with any technological difficulties. 
 
Interview 
Following informed consent/assent, confirmation of diagnosis of ENPP1 deficiency or 
the acute form of ABCC6 deficiency, and group assignment based on disease and growth 
status (e.g. still growing or no longer growing), study participants will be scheduled for a 
40 to 60-minute interview administered via telephone by trained interviewers, conducted 
in their native language or in English (language is selected by the participant). During the 
interview, the interview staff will enter the respondent’s answers to the questions to 
Engage Health’s proprietary, HIPAA compliant study module. As part of this process, the 
information provided in the RSVP disease and growth status will drive "skip logic" in 
order to ensure that questions will only be asked of participants to whom they pertain. If 
the participant does not wish to answer any question in the study, they will be given the 
option to abstain. If the participant wishes to discontinue the study, they will be allowed 

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to stop at any time. If the participant agrees, the interview will be recorded and stored in a 
pseudonymized fashion as an MP3 file in Engage’s proprietary, HIPAA compliant 
servers.  
 
Participants will be asked, in an un-aided fashion, about key burdens related to their/their 
child’s disease, as well as the life impacts of those burdens for the patient and family. All 
of the respondent’s answers are considered “Anonymous Data”. 
 
Remuneration 
At the completion of each interview, the participants will be paid $100 honoraria. A 
choice will be given for the participant to select a $100 check paid in US dollars and 
mailed by Engage Health, or an e-gift card to Amazon.com sent by email by Engage 
Health.  
 
Discontinuation of a participant 
Engage Health, Inc., the health research vendor, or the sponsor may discontinue the 
participant if it is in the participant’s best interest, the participant does not consent to 
potential changes made in the study plan (if applicable), or the participant does not keep 
the scheduled appointment for the telephone interview. 
 
Quality Control (QC) 
At the completion of the interviews, the data will be reviewed for clarity and 
completeness, and interview tapes will be accessed if the participant consented to 
recording. If there is a need for additional information, the participant will be contacted 
by Engage Health to clarify the data. Any data that is not able to be clarified will be 
flagged as an outlier and that data will not be available for analysis.  
 
At the completion of the QC, Engage Health will download all Study Data (the 
combination of Personal Data and Anonymous Data) and pseudonymize the Personal 
Data, removing all identifying information and assigning each patient a unique identifier. 
The log of unique identifiers will be stored separately from the anonymized data. When 
this is completed, the database will be locked.  
 
Analytic Plan 
As described above the pseudonymized answers provided by each respondent will be 
combined with those of others participating in the study and the pseudonymized database 

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(Excel format) will be locked and provided to Engage Health personnel for analysis 
(“Study Data”). The goal of the thematic analysis is to uncover patterns and trends that 
provide both evidence and context for experiences and disease burdens reported by 
patients and families impacted by ENPP1 deficiency (GACI or ARHR2) or the acute 
infantile form of ABCC6 deficiency. 
 
In this analysis the combination of an inductive and deductive approach will be used to 
assess each study subgroup  
• 
Inductive Approach: First, each participant will be asked about the burden of 
access to them/their child, as well as the life impact. Information will be gathered 
in the words of the participant.  
o At the conclusion of the interviews, the information will be assessed 
from a latent perspective, with two independent coders reviewing the 
comments, subtext and related discussion to determine the theme. If there 
is not agreement between the coders. A third party trained in coding will 
independently assess and make a determination. 
o In order to ensure data is representative, the study will ensure saturation 
of themes for each subgroup. To do this, the first 5 respondents in each 
subgroup will be considered the baseline group. Recruitment will be 
purposive with each subsequent group of five considered a cohort.  
▪ 
The first cohort will be compared to the baseline; if any themes 
are raised that were not raised by the baseline group, saturation 
will not have been met, and recruitment will continue.  
▪ 
The second cohort will be compared to the baseline group plus 
the first cohort, if any themes are raised that were not raised by 
the baseline group, saturation will not have been met, and 
recruitment will continue.  
▪ 
The sponsor intends to recruit as many patients as possible to 
fully understand the burden of disease. However, given the rarity 
of these conditions, recruitment may end when the subgroup 
cohort does not raise any new themes that are meaningful and 
important compared to the previous groups.  
• 
Deductive Approach: Prior to the interviews a list of burdens that are expected 
from each group will be compiled by the research team and will be reviewed by 
the participant after the questions are asked in an un-aided way. This will allow 
the participant to review the list and provide a different answer, information 

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about participants who changed their answer will be described as a descriptive 
statistic.  
 
All findings will be summarized in the final report, which will not identify any 
respondent as described above. At the conclusion of this study, the researchers may 
publish their findings in a medical / scientific journal. 
 
Data Collection and Storage 
The following procedures will be used to protect the confidentiality of study data.  
The RSVP information will be entered by the study participant into the RSVP site. 
Validated questionnaires will be printed and filled out by the participant. These, along 
with the “Proof of Disease Form” will be uploaded or otherwise provided to Engage 
Health. The interview data will be entered by the interviewer into the data collection site 
and system allows these data to be appended to the RSVP answers previously provided 
by the participant.  
PRO Tool forms that have been filled out by the patient and uploaded to Engage Health 
will be pseudoanonymized as described above and sent to Inozyme for scoring via secure 
data transfer system or encrypted e-mail.  
The electronic records reside on secure encrypted servers that are wholly owned by 
Engage Health. All data collected will be pseudoanonymized as described above, stored 
in a locked / secure location and stored on secure wholly-owned servers for a period of 
time consistent to permit study-related monitoring, audits, and analysis by providing 
direct access to all study records.  
 
Despite the fact that Engage Health is not a covered entity under HIPAA, appropriate 
administrative, technical, and physical safeguards to protect the privacy of protected 
health information are employed at all times. 
 
To review the privacy and data storage policies of Engage Health Inc. and a discussion of 
HIPAA compliance, study participants may visit http://www.engagehealth.com/privacy-
policy/ or contact the Data Privacy Officer at dataprivacyofficer@engagehealth.com.  
 
Study participants will be notified that the Institutional Review Board (IRB) may inspect 
study records as part of its auditing program, but these reviews will only focus on the 
researchers and not on their responses, their personal information or involvement. 
 

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Number of participants (planned):  
Target: 60; Minimum: 30; Maximum: 90. Study recruitment will be purposive, seeking 
to initially recruit 60 respondents, 20 respondents from each of the three groups with a 
minimum of 30 and maximum of 90;  
 
60 participants across four groups; person or parent/legal guardian affected by ENPP1 
(GACI or ARHR2) or the acute form of ABCC6 deficiency as described below;  
• 
Acute infantile ENPP1 deficiency (note; due to the high infant mortality, this 
group is likely to include parents of affected children, both living and deceased) 
• 
Acute infantile ABCC6 deficiency (note; due to the high infant mortality, this 
group is likely to include parents of affected children, both living and deceased) 
• 
Progressive pediatric ENPP1 deficiency who are still growing (note; due to the 
age of those who are still growing, this group is likely to include parents of 
affected children) 
• 
Adult ENPP1 deficiency who are no longer growing (note: due to the age of 
those who are no longer growing, this group is likely to include both patients > 
age 18 years and parents of affected children who are < age 18 years or who are 
unable to answer for themselves) 
 
In order to get a geographic sampling, the respondents will be recruited from countries 
where individuals speak English, French or German (likely to be the US, Germany, the 
UK, Canada, Australia and France).  
Inclusion Criteria  
Subjects eligible for enrollment in the study must meet all of the following criteria: 
1. Participant must be a person with ENPP1 deficiency or the acute infantile form of 
ABCC6 deficiency who is 18 years or older  
or  
2. The parent/caregiver of a patient who has been diagnosed with ENPP1 deficiency or 
the acute infantile form of ABCC6 deficiency. Please note, parents/caregivers of 
patients with ENPP1 deficiency who have passed away may participate 
3. Confirmed diagnosis of ENPP1 deficiency or ABCC6 deficiency with written proof 
of disease provided 
4. Ability to participate in the RSVP and interview in German, French or English, 
irrespective of country of residence.  

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5. Able to grant informed consent 
6. Willing to participate in a 40-to-60-minute telephone interview, including follow up 
questions (if necessary)  
Exclusion Criteria  
1. Inability to meet any of the inclusion criteria 
Investigational product, dosage, and mode of administration:  
Not applicable  
Duration of study  
This is a one-year study. Each participant will participate in a single interview. Recruitment 
of participants and caregivers to be interviewed, and the start of the interviewing process 
should begin in 2Q 2020 and complete in 4Q 2020. Analysis and report should be completed 
by 4Q 2020. 
Participating countries 
Any patient who can speak English, German or French. (Likely patients to reside in 
Germany, France, Australia, the UK, Canada, and the U.S.)  
Name, Address and Phone of Sponsor’s Medical Expert / Principal Investigator:  
Pedro Huertas, MD, PhD                
Chief Medical Officer 
Inozyme Pharma Inc.            
280 Summer Street 
Boston, MA 02210 
 
Phone:  +1.857.800.0356 
Mobile: +1.978.394.5700 
Email :   pedro.huertas@inozyme.com 
Web :   www.inozyme.com 
 
Statistical methods:  
The data for each question in the study will be analyzed and reported by Engage Health using 
descriptive statistics as appropriate for the nature of the data collected—frequency 
distributions, cross-tabulations, and measures of central tendency and dispersion. 

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Study risks:  
This research study is not associated with any known risks; Time to complete the RSVP and 
interview may be as a possible inconvenience. Each respondent will need up to approximately 
60 minutes for the entire process; 20 minutes to complete the RSVP including uploading the 
proof of ENPP1 deficiency or ABCC6 deficiency diagnosis, and approximately 40 minutes to 
complete the interview and address any follow-up questions if needed. 
 
While Engage Health makes every reasonable effort to protect the information it collects 
study participants will be made aware there is always some risk involved when submitting 
Personal Data over the internet. We cannot guarantee that the RSVP site and servers are 
100% safe from illegal tampering or “hacking.” However, once Study Data is received at 
Engage Health and entered into the database, any data submitted has the same protection that 
Engage extends to its own confidential information. 
Study benefits: 
Research participants may not benefit directly from this research; however, it is hoped that 
participation in the study will provide a better medical understanding of the ways that ENPP1 
deficiency and acute ABCC6 deficiency disease impacts families in terms of disease burden 
and quality of life.  
 
 
 
 

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