Specialist outreach: adults with X‑linked nephrogenic diabetes insipidus
Recruitment support for NCT07525960 — a Phase 1b study in men aged 18 to 55 with AVPR2 variants
Generated 2 September 2026
Prepared by Alex Tamayo-Wolf
Source NDIF outreach register
Figure 1. Disposition of discovered specialists (n = 154)
Every address in the register was read from a named published source. None were
inferred from naming conventions, a decision validated when two institutions were found to use
irregular formats.
0154
Contacted — 83, of which 2 have replied
Address verified, ready to contact — 5
Discovered, no published address — 66
Table 1. Coverage by jurisdiction
Jurisdiction
Discovered
Contacted
Ready to contact
Remarks
Washington
52
42
0
Every reachable contact emailed
Florida
43
15
0
Jacksonville trial site
Texas
17
10
0
San Antonio trial site
Utah
11
5
4
Division leadership complete
California
11
5
0
Addresses largely withheld
Oregon
5
1
1
Arizona
4
2
0
Colorado
4
2
0
New Mexico
4
0
0
Leadership named only
United Kingdom
1
1
0
Quebec
1
0
0
Nevada
1
0
0
No academic division exists
Total
154
83
5
Replies received
Two of eighty-three contacts have replied, both on 2 September.
Fouad Chebib, MD — Mayo Clinic, Jacksonville
I am engaged with this study and have few patients. Thanks for your efforts
to help us recruit.
He is already involved in this trial and holds candidates, so Mayo Jacksonville is a
participating relationship rather than a cold contact.
Aylin Rodan, MD, PhD — Chief of Nephrology, University of Utah
I've forwarded your email to our nephrologists, and to our Pediatric Nephrology
division chief, since they may have a few young adults.
She circulated the request across her division unprompted, and arrived independently at a
conclusion we had also reached: men with this condition were paediatric patients long before
they were adults, so paediatric nephrology may know where they are.
Contacts of highest relevance
Ranked by proximity to the disease mechanism and to the trial sites, not by seniority.
Fouad Chebib, MD — Mayo Clinic, Jacksonville
Published in 2026 on the regulation of aquaporin‑2, one of the two proteins whose failure
causes this disease. Located in the trial site city. Contacted 25 August; replied 2 September.
David Ellison, MD — Oregon Health & Science University
Career focus on inherited disorders of renal salt and water transport, the same disease
family as NDI. Directs Oregon's clinical and translational research institute. Contacted 25 August.
Charles Heilig, MD — UF Health Jacksonville
Chief of nephrology and fellowship director in the trial site city. Contacted 20 August.
Kumar Sharma, MD — UT Health San Antonio
Divisional chief at the second trial site; leads a national precision medicine programme
in kidney disease. Contacted 20 August.
Daniel Bichet, MD — University of Montreal
First to identify AVPR2, the gene responsible for this condition. Outside the US and so not
a referral source, but unmatched in standing and network. No published address located.
Candidates discovered in internal records
Running in parallel with the specialist search, a review of NDIF's own patient survey and
subscriber list identified 12 men who may meet the eligibility criteria. Eleven households
have been contacted; one had already registered independently. This review required no external
research and has produced more prospective candidates than the specialist campaign to date.
Notes
Both replies came from contacts selected for proximity to the disease rather than for
seniority, which is early evidence that the ranking is sound.
One message was undeliverable in substance: the recipient at Utah has left the institution.
His automatic reply named two successors, one of whose addresses is now confirmed and ready
to contact.
Access to addresses, not willingness to send, remains the binding constraint. Sixty-six
discovered specialists have no published address; the institutions concerned withhold them as
a matter of policy. Training programme pages have proved the most reliable source and are now
checked first at every new centre.
All recipients are directed to screening.ndif.org. NDIF conveys information only;
eligibility is determined by the study sites.