Yes, it’s possible, here’s how:
1. Create a public/private key pair and use the public key to encrypt the data that you want to share.
2. Encrypt the private key using the user public keys that you want to share the data with.
3. Save the encrypted private key to your database.
4. When you want to share the data with other users, also encrypt the private key with these new users’ public keys. This way, you won’t have to re-encrypt the data, but rather, share the key by encrypting it with the user public keys.