Marijuana has no currently accepted medical use in treatment in the United States: The FDA has not yet approved an NDA for marijuana. The opportunity for scientists to conduct clinical research with marijuana exists under the HHS policy supporting clinical research with botanical marijuana.

While there are INDs for marijuana active at the FDA, marijuana does not have a currently accepted medical use for treatment in the United States, nor does it have an accepted medical use with severe restrictions. A drug has a ‘‘currently accepted medical use’’ if all of the following five elements have been satisfied:

a. The drug’s chemistry is known and reproducible;
b. There are adequate safety studies;
c. There are adequate and well-controlled studies proving efficacy;
d. The drug is accepted by qualified experts; and
e. The scientific evidence is widely available.

[Alliance for Cannabis Therapeutics v. DEA,
15 F.3d 1131, 1135 (D.C. Cir. 1994)]

Although the structures of many cannabinoids found in marijuana have been characterized, a complete scientific analysis of all the chemical components found in marijuana has not been conducted.

A material conflict of opinion among experts precludes a finding that marijuana has been accepted by qualified experts. At this time, it is clear that there is not a consensus of medical opinion concerning medical applications of marijuana.

Finally, the scientific evidence regarding the safety or efficacy of marijuana is typically available only in summarized form, such as in a paper published in the medical literature, rather than in a raw data format. As such, there is no opportunity for adequate scientific scrutiny of whether the data demonstrate safety or efficacy.

....a material conflict of opinion among experts precludes a finding that marijuana has been accepted by qualified experts, even under conditions where its use is severely restricted. To date, research on the medical use of marijuana has not progressed to the point that marijuana can be considered to have a ‘‘currently accepted medical use’’ or a ‘‘currently accepted medical use with severe restrictions.’’

They won't even concede its safe if taken under medical supervision:

If marijuana is to be investigated more widely for medical use, information and data regarding the chemistry, manufacturing, and specifications of marijuana must be developed. Therefore, HHS concludes that, even under medical supervision, marijuana has not been shown at present to have an acceptable level of safety.

So marijuana will remain a Schedule I controlled substance, which means the feds continue to maintain:

A. The drug or other substance has a high potential for abuse.
B. The drug or other substance has no currently accepted medical use in treatment in the United States.
C. There is a lack of accepted safety for use of the drug or other substance under medical supervision.

Update: What about the statements of medical marijuana users attesting to the relief from pain they experience? They don't count.

Scientists call [stories by marijuana users who claim to have been helped by the drug] anecdotes. They do not accept them as reliable proofs. The FDA’s regulations, for example, provide that in deciding whether a new drug is a safe and effective medicine, ‘‘isolated case reports will not be considered.’’ 21 CFR 314.126(e).

Why do scientists consider stories from patients and their doctors to be unreliable? First, sick people are not objective scientific observers, especially when it comes to their own health. [. . .] Second, most of the stories come from people who took marijuana at the same time they took prescription drugs for their symptoms. [. . .] Third, any mind-altering drug that produces euphoria can make a sick person think he feels better. [. . .] Fourth, long-time abusers of marijuana are not immune to illness.

The good news, according to Americans for Safe Access, is now that the DEA has acted to reject the petition, the matter can finally go to a federal court for determination. The timing shows no help can be expected from the Obama Administration:

Notably, the petition denial was sent to legal counsel in the pending lawsuit on June 30th, one day after the Justice Department issued a memorandum to U.S. Attorneys upholding federal threats of criminal prosecution against local and state officials for attempting to pass and implement their own medical marijuana laws. "The federal government is making no bones about its aggressive policy to undermine medical marijuana," said ASA Executive Director Steph Sherer, "And we're prepared to take the Obama Administration to court over it."

The denial also comes the same week as the International Cannabinoid Research Society (ICRS) is holding its 21st annual symposium in St. Charles, Illinois, just outside of Chicago. The symposium is sponsored in part by an array of pharmaceutical companies, the U.S. National Institute on Drug Abuse (NIDA), and ElSohly Laboratories, Inc., the federal government's only licensed source of research-grade cannabis (marijuana) used in therapeutic studies. Currently, several pharmaceutical companies are asking the government to reschedule organically produced THC, the primary compound found in the marijuana plant, so they can sell a generic version of Marinol®, which is now made synthetically.

Here is the federal lawsuit filed in May in the DC Circuit Court of Appeals to force the DEA to rule on the petition to reclassify. The issue:

Whether the DEA's delay of nearly nine years in providing a substantive response to petitioners' marijuana rescheduling petition-and almost five years after receiving a 41-page memorandum from HHS stating its scientific evaluation and recommendations constitutes unlawful withholding or unreasonable delay of agency action, thereby warranting relief under Section 706(1) of the Administrative Procedure Act and the All Writs Act, 28 U.S.C. § 1651(a).

The original petition is here, and the Americans for Safe Access backgrounder is here.