I believe so.
Doesn't worry me at all. Here's why, as I understand it...
Drug companies may view many potential uses, and therefore many potential income streams, for a drug under development. Therefore, going into initial clinical trials, they have to make a strategic decision. If they test broadly for multiple conditions and receive broad FDA approval, they can maximize profits. At the same time, if the drug proves effective for some conditions but not all, and they don't receive FDA approval, they have to refine their trials and start from scratch. In other words, if the company gets over-confident and greedy, their trials could flame out and the drug gets delayed.
On the other hand, if their initial trial is limited, designed for the lowest hanging fruit, the condition easiest to prove, then they maximize potential for earliest approval. With the drug on the market, they can then run additional trials for additional conditions and receive additional approvals if those trials are also successful.
Why I'm not worried that the drug isn't being tested primarily for tinnitus-related efficacy, is that once it's approved for any condition, it's available off-label any way your doctor wants to prescribe it. Therefore, assuming it helps tinnitus, the path of least resistance may be to establish efficacy for another condition that's easier to prove first, bringing it to market -- bringing it to us -- as fast as possible.
The company could then follow up with additional trials for tinnitus that, if approved, makes it reimbursable, but if not approved (if not effective to FDA standards, but still helpful to some subset of tinnitus sufferers), doesn't remove the drug from the market.