diff --git a/packages/remix-fastify/src/server.ts b/packages/remix-fastify/src/server.ts
index 8e9c8617..c8afc734 100644
--- a/packages/remix-fastify/src/server.ts
+++ b/packages/remix-fastify/src/server.ts
@@ -71,6 +71,7 @@ export function createRemixHeaders(
   let headers = new Headers();
 
   for (let [key, values] of Object.entries(requestHeaders)) {
+    if (key.startsWith(":")) continue;
     if (values) {
       if (Array.isArray(values)) {
         for (let value of values) {