Most independent sites have tried it: find a study that looks like a fit, find an email address for the sponsor, and write to say your site is interested. Then nothing happens. When you do get an answer, it is often a single line that doesn't seem to help.
Only a small fraction of site-interest emails get a reply from a person. That isn't a judgment on your site. It mostly reflects how and when sponsors choose sites. Once you understand what the common replies mean, you can spend your time on the emails that have a real chance.
What the common replies really mean
"Site selection is complete"
This is the most useful answer you can get, even though it is a no. It tells you the sponsor has already picked its countries and sites for this study. ClinicalTrials.gov shows a study once it's public, and by then the sites have often already been chosen. US rules allow applicable clinical trials to register as late as 21 days after the first participant enrolls, so a listing can trail site selection.
What to do: thank them, ask to be considered if the study adds sites later, and note the date. A study that later adds locations or pushes out its completion date may reopen selection.
"This study is fully outsourced to a CRO"
A contract research organization (CRO) is managing feasibility or site identification, though the sponsor may still approve the final site list. The person who answered may genuinely have no say over sites.
What to do: ask, politely and once, which CRO is running feasibility, or whether they can forward your details. Then approach the CRO's feasibility or site-identification team with the same short, specific message. Many CROs keep their own site databases, so registering there can matter more than the email. Some sponsors also use shared investigator platforms, so keep your profile current wherever you're registered.
"Please register through our portal"
Many larger sponsors and CROs route site interest through a site-registration portal or a general research inbox.
What to do: register, and do it properly. Fill in every field about your therapeutic areas, PI experience, equipment and patient access, and keep the profile current. A thin portal profile is easy to skip. Treat the portal as the front door, not a brush-off.
"We'll keep your details on file"
This usually means there is nothing open right now. It can be sincere, but a file rarely calls you back on its own.
What to do: keep a short record of who replied and when, and write again only when there is a new, specific reason, such as a new study in the same program.
No reply at all
Silence is the most common outcome. The address may be a shared inbox, the person may have moved on, or the study may be past selection.
What to do: one polite follow-up after a week or two is reasonable. After that, stop and wait for a new reason to write.
Why so few emails get answered
A few patterns explain most of the silence:
- Timing. Site selection is often well advanced before a study is visible publicly. An email about a public study can arrive after the decisions are made.
- Wrong door. The people listed on public pages are often not the people who choose sites, and many studies are run through CROs.
- Generic messages. "We are a research site interested in your studies" gives a busy study team nothing to act on.
- Volume. Study teams receive many unsolicited messages, and they answer the ones that solve a problem they have today.
When to write anyway
An interest email is worth sending when you can answer yes to most of these:
- The timing is plausible. The study is not yet recruiting, is adding locations, or has had its completion date moved later, which can be a sign that enrollment is slow. None of these confirms that site selection is open, so ask. Earlier signals, such as a sponsor's funding round or positive Phase 2 results ahead of a next study, are leads worth checking.
- You can name one specific protocol. Write about one study, not the sponsor's whole pipeline.
- You fit that protocol. Your PI has relevant experience, you have the procedures and equipment, and you can give a realistic estimate of potentially eligible patients, as aggregate counts only, from records your team is authorized to review, with your assumptions stated.
- You can write to the right team. Clinical operations, feasibility or site identification, at the sponsor or at its CRO.
What a good interest email looks like
Keep it short enough to read on a phone:
- Subject: the NCT number or protocol number, a short title, and your site's city.
- First line: why you are writing about this study, today.
- Fit in three points: PI experience in the indication, the key procedures and equipment you have, and an aggregate patient estimate.
- One attachment at most: a one-page site summary.
- A clear, easy ask: whether site selection is still open, and who handles feasibility.
- Be ready to move fast: be able to sign a CDA and return a feasibility questionnaire within days, with current PI CVs, GCP certificates and medical licenses on hand.
Never include patient information or confidential materials from other studies, and don't promise enrollment numbers you can't support.
How Shortlisted™ approaches this
Timing is the part most sites can't fix on their own, which is why we built our Trial Radar to watch for earlier signals that a study may need sites, and to check each one against a site's real capabilities before anything is sent. In the 6-Month Site Pilot, we draft the outreach and you approve it, and every contact goes into a shared log you can see. Shortlisted™ is paid only by sites, never by sponsors or CROs. There is no setup fee and no monthly retainer; a fixed fee becomes payable only when a qualified feasibility arrives, and it is never tied to enrollment, patient numbers or study budgets. We support your site's outreach; we don't refer patients or guarantee a place in any study. We can't promise a sponsor will reply or select your site.
If you'd like to see how your site looks to a study team today, start with a free Sponsor-Ready Audit.
The short version
Most interest emails go unanswered because they arrive late, go to the wrong team or say too little. Read the replies you do get as information about timing, register where you're told to, and write when you have a specific protocol, a real fit and a plausible window.
FAQ
Why don't sponsors reply to site-interest emails?
Usually because of timing (sites are often chosen before a study is public), because the email reached someone who doesn't choose sites, or because the message wasn't specific enough to act on. Only a small fraction of these emails get a reply from a person.
What does "site selection complete" mean?
The sponsor has already chosen its countries and sites for that study. Ask to be considered if it adds sites later, and watch for signs that it is adding locations or extending its timeline.
What should I do when a sponsor says the study is outsourced to a CRO?
Ask once which CRO is handling feasibility, then contact that CRO's feasibility or site-identification team and register in its site database if it has one.
How many times should I follow up?
Once, after a week or two. After that, wait for a new, specific reason to write, such as a new study in the same program.