SQLite query with location fields inside of region

I have a database with two columns, latitude and longitude. I wonder if it's possible in the Transact-SQL command to retrieve only the records in a defined region of the location passed as a parameter;

For example let's say you have the following records, which is all from the same location, but we're using them for testing purposes.

Now I have the SQL query:

[self.fmQueue inDatabase:^(FMDatabase *db)
    {
    CLLocationCoordinate2D center = CLLocationCoordinate2DMake(latitude, longitude);
    CLCircularRegion *region = [[CLCircularRegion alloc] initWithCenter:center radius:400.0f identifier:@"identifier"];

    NSString* queryCommand = [NSString stringWithFormat:@"SELECT * FROM %@ WHERE ?EXPRESSION_ABOUT_REGION?", readingsTable];
    FMResultSet* result = [db executeQuery:queryCommand];
    if (completionblock)
        {
        completionblock([self readingsArrayFromResultSet:result]);
        }
    }];

I could just retrieve records and then compare for every each one with a constructed CLLocationCoordinate2D, [region containsCoordinate:CLLocationCoordinate2D], but that feels so bad performant.

I'm looking for the most performant and appropriate solution to retrieve the desired region related location records in the T-SQL query.