Dihydralazine

Hypertension is one of the chronic cardiovascular diseases with the highest prevalence worldwide. For patients with refractory hypertension complicated by renal insufficiency, the efficacy of conventional antihypertensive drugs often fails to meet the treatment target. Dihydralazine belongs to the hydralazine class of peripheral vasodilators. It exerts an antihypertensive effect by directly relaxing the smooth muscle of small arteries and reducing peripheral vascular resistance. Meanwhile, it has little impact on venous vessels and does not significantly increase the risk of orthostatic hypotension. It is often clinically formulated into compound preparations with diuretics and β-receptor blockers for the treatment of patients with moderate to severe hypertension, renal hypertension and high diastolic blood pressure. It can also be used as an alternative option for patients with gestational hypertension who are intolerant to first-line drugs, and its medication safety has been verified by long-term clinical practice.

From the perspective of the global market, as a classic antihypertensive drug, dihydralazine has entered a stable period in terms of market size. In 2023, the overall global market size was approximately USD 120 million, of which generic drugs accounted for more than 95%. Driven by the growing demand for compound antihypertensive preparations in the domestic market, the annual compound growth rate of the market in the past three years has maintained at around 4.7%. The current competitive landscape is dominated by domestic generic drugs, with more than 10 enterprises having obtained preparation approvals. The supply of active pharmaceutical ingredients (APIs) has basically achieved localization, and dihydralazine has not been included in the national centralized drug procurement scope, so its price system is relatively stable. If there is no verifiable data, the above market data are for reference only.

The original research enterprise of dihydralazine is Novartis, with the original brand name Apresoline®. The core compound patent expired globally in 1959. At present, the main dosage form of the original drug marketed worldwide is tablets, with specifications including 10mg, 25mg, 50mg and 100mg, which has been included in the FDA Reference Listed Drug Catalog. No original preparation has been approved for import in China yet. Currently, there are 8 registration numbers of dihydralazine APIs on the CDE API Registration Platform, of which 5 are in activated status (Status A). 3 varieties of domestic preparations have been approved for marketing, namely dihydralazine tablets, compound reserpine and dihydralazine tablets, and valsartan and dihydralazine tablets. (The data are as of June 2025, please refer to the official CDE website for the latest information.)

CATO provides a full set of impurity reference standards for dihydralazine API, which can cover the demand for all known and unknown impurity reference standards that may be generated during the synthesis and degradation processes. Most products are in regular stock, and orders placed before 16:00 can be shipped on the same day. All products comply with the pharmacopeia of China, FDA and other national drug regulatory regulations, and can provide reliable reference standard support for API and preparation enterprises in quality research, stability test, registration declaration and other work.